Euro S50 Single Vanos
The following information is for reference purposes only, and you should use it at your own risk.
In no event shall Beisan Systems, LLC or its members be liable for incidental, consequential, or special loss or damages of any kind however caused. However, it is important to note that this limitation of liability is a standard practice in many agreements. Additionally, companies often include such clauses to protect themselves from unforeseen or excessive claims.
Therefore, while this provision may seem restrictive, it serves to balance the responsibilities between the parties involved. Furthermore, users should carefully review these terms to fully understand their rights and obligations. In conclusion, clear communication and transparency are essential to ensure mutual understanding and fairness.
Introduction
“Vanos” is BMW’s name for its variable valve timing units. Vanos units take on various shapes and design according to car year and model (engine model).
The VANOS discussed here is BMW part #11-31-1-402-428. Specifically, it is a single VANOS system, meaning only the intake valve timing is varied. This particular VANOS unit is part of the BMW 6-cylinder engine Euro S50B30. Notably, BMW incorporated this engine into only one car model, the 3-series Euro E36 M3, which they produced between 1993 and 1995.
However, this VANOS system has been experiencing failures. As a result, it is important to address the issue to ensure optimal engine performance and longevity. For instance, common symptoms of VANOS failure include rough idling, loss of torque, and reduced fuel efficiency. Therefore, diagnosing and repairing the system promptly is crucial for maintaining the vehicle’s performance.
Diagnostics show that the failure is primarily due to the deterioration of the vanos intake rod seal.
Engineers have identified that manufacturers make this cup seal from Buna rubber (Buna-N, NBR, Nitrile).
Buna is a very common rubber material but has limited temperature and chemical resistance characteristics.
Unfortunately, the seal is performing poorly in the Vanos/engine environment. Over time, observations show that the seal hardens, shrinks, and develops flat surfaces.
As a result of this deterioration, the seal loses its functional characteristics. This, in turn, leads to the failure of the VANOS system, causing potential performance issues and requiring maintenance or replacement.
Historically, BMW has discussed other VANOS failures in the past, but the company has decided not to address these issues further. In fact, BMW has explicitly stated, “We will not pursue further development.”
his decision highlights a lack of commitment to resolving the ongoing problems with the VANOS system. As a result, owners of affected vehicles must deal with the consequences, such as reduced engine performance and potential repair costs.
Ultimately , this stance by BMW may lead to dissatisfaction among customers, as they expect long-term reliability from their vehicles.
Furthermore , BMW does not provide the vanos rod seal as a separate part, which complicates repairs and maintenance.
To address this , replace the Buna rod seal with a Viton rubber rod seal, as it offers superior durability and performance in the vanos/engine environment.
Although Viton (FKM, Fluorocarbon) has similar functional characteristics to Buna, it boasts much higher temperature and chemical resistance.
However , an even better solution is to replace the rod seal with a Teflon equivalent.
This is because Teflon (PTFE filled) has significantly lower friction properties, making it far more suitable for dynamic sealing compared to rubber.
- It’s compatible with the engine environment and , as a result, is considered a standard material for this rod cup seal design.
- In addition , an O-ring is inserted into the cup to provide energizing support for the Teflon.
- Furthermore , Viton is the best material for the O-ring because it can effectively withstand the harsh conditions of the engine environment.
The vanos intake piston seal can also in some cases experience a problem.
This seal consists of a Teflon ring and a backing machined Viton rubber ring. Over time , the seal can lean to one side, which in turn causes uneven wear of the Teflon ring.
Two primary factors cause this issue. Firstly , the failure of the rod seal leads to oil leakage from one side of the piston seal. Consequently, the oil chamber on the opposite side of the piston seal exerts pressure against the seal, causing it to tilt.
As a result, the seal loses its functionality, which leads to further deterioration of the VANOS system. Therefore, addressing these underlying factors is crucial to preventing premature failure and ensuring the system operates as intended.
Second, the piston seal cavity is too wide and facilitates the space for the seal to tilt. The issue arises when a paper gasket is placed between two piston parts, which widens the cavity.
This paper gasket functions to maintain the piston parts from spinning during assembly, but has no function after assembly.
To solve the piston seal problem, replace the rod seal with a more durable seal that prevents oil chamber leaks.
Additionally, removing the paper gasket restores the piston seal cavity to its correct width and eliminates excess space.
The vanos solenoid O-rings also fail and in some cases and cause external oil leak.
These O-rings are made from Buna, which tends to harden and flatten over time. Initially, technicians attempted to replace the Buna O-rings with Viton O-rings as a solution, but this approach has not worked. Specifically, the Viton O-rings shred under high oil pressure, rendering them unsuitable for this application.
In response to the issues identified , BMW has redesigned the solenoid O-rings for the S62 engine (E39 M5) VANOS unit.
Interestingly , the S62 VANOS solenoids are identical to those used in the Euro S50 VANOS system, which means they share the same O-rings. This redesign suggests that BMW has recognized the issue and taken steps to improve durability, though it remains unclear whether these updated components fully resolve the problem. Therefore, further testing and evaluation may be necessary to ensure long-term reliability.
The new S62 solenoid O-rings use Viton material and feature multiple facets.
This combination ensures the O-rings are both durable and highly functional in the VANOS system.
The facets divert oil flow away from the O-ring, preventing it from shredding.
By redirecting the oil flow, these facets enhance the O-rings’ longevity and reliability. As a result, the VANOS system operates more efficiently and with fewer failures.. This innovative design addresses a common issue in the Vanos system, enhancing its durability and performance.
Furthermore, the new S62 Vanos solenoid O-rings incorporate this improved design, making them highly suitable for use with this Vanos solenoid. As a result, they offer greater reliability and longevity compared to previous versions.
However, it is important to note that you must purchase these O-rings directly from BMW, as the Beisan Systems seals kit does not include them.
This means you will need to source these specific O-rings separately to complete the repair or maintenance process. This distinction highlights the need for owners to source the correct components separately to ensure proper functionality and longevity of the VANOS system. Therefore, while the Beisan kit provides a comprehensive solution for many seals, the specialized S62 O-rings remain a critical, standalone purchase for optimal performance.
The vanos also has multiple O-rings used for static sealing. All but one of the O-rings use Viton material, which is the correct choice for this application.
Viton offers excellent resistance to heat and chemicals, ensuring the O-rings perform reliably in the VANOS system. As a result, they help maintain the system’s functionality and longevity.
But over time they experience compression set (flattening) and need replacement.
You can replace the static sealing O-rings with a set of Viton O-rings.
Additionally, you can purchase a VANOS seals/O-rings repair kit from Beisan Systems (pronounced “bee-saan”) at www.beisansystems.com/products.
This kit provides a convenient solution for maintaining and repairing the VANOS system.
This kit includes several key components: first , a VANOS replacement intake rod Teflon cup seal with an inserted Viton O-ring; in addition , an intake piston seal composed of a Teflon ring and a machined Viton rubber ring; and finally , a replacement set of static Viton O-rings.
These components specifically address common failure points within the VANOS system, such as seal deterioration, oil leakage, and uneven wear.
By using these high-quality parts, you can prevent frequent issues and extend the lifespan of your VANOS system. As a result, your vehicle will maintain better performance and reliability. By replacing these critical parts, the kit aims to restore the VANOS system’s functionality, improving engine performance, throttle response, and overall reliability.
Additionally, the use of high-quality materials like Teflon and Viton ensures greater durability and resistance to the high-pressure environment of the VANOS system. Therefore, this repair kit provides a comprehensive solution for maintaining or restoring the optimal operation of your VANOS unit.
Symptoms of a failing Euro S50 Single VANOS system may include:
- Loss of low-end torque, making the car feel sluggish at lower RPMs.
- Rough idling or unstable engine performance when the vehicle is stationary.
- Reduced fuel efficiency, as the engine struggles to maintain optimal timing.
- Hesitation or jerking during acceleration, particularly at lower speeds.
- Unusual noises from the VANOS unit, such as rattling or ticking sounds.
By addressing these issues with the Beisan Systems repair kit, you can restore the VANOS system’s performance and improve the overall driving experience. However, it is important to follow the installation instructions carefully to ensure proper functionality.
Cars experience:
Overall loss of torque and power, particularly in the lower RPM range, < 3k. Bogging then surging at 3k RPM. Uneven power distribution and RPM transition. Engine hesitations in the lower RPM range, < 3k. Louder idle and intermittent idle RPM hiccups. Difficult takeoffs. Loss of power and bogging when AC on. Increased fuel consumption.
Repairing the vanos seals provides:
Overall increase in torque and power, particularly in the lower RPM range, < 3k. Resolution of bogging then surging at 3k RPM. Smooth even distribution of power and RPM transition. Resolution of engine hesitations in the lower RPM range, < 3k. Quiet stable idle. Smooth easy takeoffs. Improved performance when AC on. Reduced fuel consumption.
Diagnosis
In general, a diagnosis is not necessary. The vanos Buna intake rod seal deteriorates in 20k miles (32k kilometers). Thus essentially all the cars with this vanos have deteriorated intake rod seal and a failing vanos.
Repair Procedure
The following is a Euro E36 M3 single vanos seals R&R (remove and replace) procedure.
The valve cover gaskets and bolt grommets on the Euro S50 engine use Viton material, ensuring they do not fail and eliminating the need for replacement.
Because of this high-quality material, these components are highly durable and reliable. As a result, they provide long-lasting performance without requiring frequent maintenance.
Repair Time:
- For a mechanic, the repair typically takes about 5 hours.
- For a DIYer, the repair may take 7 or more hours.
Parts, Tools, and Shop Supplies:
Parts with the part number pattern xx-xx-x-xxx-xxx are BMW components, and you can purchase them from a BMW dealership.
However, Beisan Systems only provides the VANOS seals repair kit.
Euro S50 single vanos seals repair kit (BS031) $60/each (www.beisansystems.com)
The kit includes the following solenoid O-rings:
- 2 x large solenoid O-rings (BMW part #11-36-7-830-828) priced at $2.29 each.
- 2 x small solenoid O-rings (BMW part #11-36-7-830-829) priced at $3.38 each.
Note that these solenoid O-rings come from the BMW S62 (E39 M5) VANOS system. Furthermore, engineers have redesigned these O-rings with multiple facets to prevent high oil pressure from shredding them.
Moreover, they use Viton as the material, which was chosen for its ability to withstand high engine temperatures and resist degradation from synthetic oil. This redesign ensures greater durability and reliability, addressing a common failure point in the VANOS system. Therefore, these O-rings are a critical upgrade for maintaining the long-term performance of your VANOS unit.
The following additional components are available for the VANOS system:
- VANOS oil filter (BMW part #11-36-1-401-973) priced at $16.27 each.
- VANOS oil filter washer (BMW part #07-11-9-963-073) priced at $0.09 each.
- VANOS solenoid cover gasket (BMW part #11-31-1-318-323) priced at $14.64 each.
- Intake splined shaft and piston self-locking nut (BMW part #11-36-1-313-170) priced at $5.42 each.
These components play essential roles in maintaining the VANOS system’s performance and reliability. For instance, the VANOS oil filter and washer ensure clean oil flow, preventing debris from damaging internal components. Meanwhile, the solenoid cover gasket provides a proper seal to prevent oil leaks. Additionally, the self-locking nut secures the intake splined shaft and piston, ensuring stable operation. By replacing these parts as needed, you can help extend the lifespan of your VANOS system and avoid potential failures. Therefore, these components are valuable additions to any VANOS repair or maintenance plan.
We recommend the following tools for performing VANOS system repairs or maintenance:
Hand Tools:
- 2 x putty knives (small and medium)
- Hammer (not shown)
- Strait pick, hook pick, 90-degree pick, razor knife, and small medium-nose pliers
Wrenches:
- 24mm combo wrench, 22mm combo wrench, 12mm combo wrench, 10mm combo wrench, and 7mm combo wrench
Screwdrivers and Miscellaneous Tools:
- Flathead screwdriver (medium head)
- Tack lifter, magnet pickup, and medium mirror
Sockets and Adapters:
- 24mm socket (1/2″, not shown)
- 10mm socket (3/8″)
- 4mm socket (6-point, 1/4″)
- 6mm hex bit socket (3/8″)
- 5mm hex bit socket (3/8″)
- 4mm hex bit socket (3/8″)
- 1/2″ to 3/8″ socket adapter
- 3/8″ to 1/4″ socket adapter
Ratchets:
- 1/2″ ratchet, 3/8″ ratchet, and 1/4″ ratchet
- 1/2″ long-arm ratchet and 3/8″ long-arm ratchet
- 3/8″ socket extension (short)
Torque Wrenches:
- Torque wrench (capable of 5 Nm [4 ft-lb] and 12 Nm [9 ft-lb])
These tools are essential for disassembling and reassembling the VANOS system with precision and care. For example, the putty knives and picks help with removing seals and gaskets without damaging surrounding components, while the torque wrench ensures proper tightening of bolts to avoid over-tightening or under-tightening. Having the right tools not only makes the repair process smoother but also helps prevent damage to the VANOS unit or engine. Therefore, assembling this toolkit is highly recommended before starting any VANOS repair project.
For the Euro S50 Single Vanos system, the BMW crankshaft turning socket (part #83-30-0-491-056) is available for $68.04 each.
However, you can substitute this socket with a 36mm 12-point socket (1/2″) if needed.
Mechanical fan removal tools include the following:
- A 32mm combo wrench, as well as a BMW water pump pulley holder (83-30-0-491-046), which costs $37.76 each.
- Additionally, a handheld sledge hammer (3lb) is required.
Note: The water pump pulley holder can also be sourced from aftermarket vendors, and it is often found on eBay. Furthermore, it is usually listed under its original BMW part number, 115030. It is often also available in a combination tool set with a 32mm slim open wrench.
First , gather the necessary materials: paper towels, a water-based cleaner (such as Simple Green diluted 1:10), brake cleaner, spray lubricant, assembly oil (lubricant oil), a parts plate, and gasket sealant.
Next , ensure that the car engine is cold before beginning the repair procedure, as this is essential for safety and proper handling.
Additionally , keep in mind that “Right” and “Left” designations are determined from the front of the car, aligned with the hood orientation.
To begin the repair process, start with the removal of the fan and shroud. Specifically, for the Euro E36 M3, follow the detailed steps outlined for fan and shroud removal.
Afterward , proceed to the removal of the valve cover, which is a critical step in the Euro S50 Single Vanos repair process.
To begin , start by taking off the engine top cover.
Following that , use a 5mm hex bit socket with a 3/8″ ratchet to remove the four cover mounting bolts.
Once the bolts are out , proceed carefully to lift off the cover, ensuring no damage occurs during removal.
First, disconnect the ignition coil electrical cable connectors.
For each coil, pull up on the coil connector’s metal lock, and then pull off the electrical cable connector.
First , eliminate the mounting bracket for the coil electrical cables.
Next , detach the two mounting nuts using a 10mm socket, 3/8″ ratchet, and extension.
Finally , remove the bracket from the mounting studs.
First, remove the coil cables’ rear boot rubber block from the valve cover.
Then, rotate the cables, bracket, and boot to the side, and wedge the boot between the air conditioning valve stem and the upper cable harness boot.
To begin , remove the coils by first removing the two mounting nuts at each coil using a 10mm socket, 3/8″ ratchet, and extension.
Next , pull up and out on all the coils to detach them completely.
Note: Be sure to maintain the coil/cylinder association for reinstallation, as this will ensure proper alignment later.
This is not necessary, but is good practice.
First , eliminate the valve cover ground wire from the rear valve cover by using a 10mm socket with a 3/8″ ratchet to remove the mounting nut.
Once the nut is removed , detach the ground wire from the valve cover stud and carefully move it toward the rear.
To start , using a 10mm socket, 3/8″ ratchet, extension, and tack lifter, remove the 16 valve cover mounting bolts with grommets located around the perimeter of the valve cover.
However , keep in mind that the rear center bolt has limited access. In this case, use a 10mm socket with a 3/8″ / 1/2″ ratchet, a 1/2″ to 3/8″ socket adapter (extension), and a tack lifter to reach it effectively.
Additionally , note that the front center bolt is shorter than the others, so take care when handling it.
First , remove the four valve cover mounting bolts with grommets located at the center of the valve cover using a 10mm socket, 3/8″ ratchet, extension, and tack lifter.
Note that these bolts are shorter than the others, so handle them carefully to avoid misplacement or damage.
To begin , remove the valve cover from the engine head.
Next , insert a blade (such as a medium putty knife) between the valve cover gasket and the engine head, and carefully pry up at all accessible locations along the front end to break the gasket bond.
Additionally , be sure to focus on breaking the sealant bond at the front corners, as these areas tend to adhere more strongly.
Repeat blade insertion and prying until cover gasket seize breaks and cover lifts. Notable prying might be needed at front center to break seize.
Note: If valve cover can not be removed, double check valve cover 16 perimeter bolts and 4 center bolts have been removed.
First , lift up and remove the valve cover from the engine head.
Next , carefully remove the valve cover perimeter gasket, ensuring it comes off cleanly.
Finally , take off the valve cover spark plug well gaskets, completing the disassembly of the gasket components.
Removal of vanos (Euro S50 Single Vanos)
Locate 4 center torx bolts on crankshaft pulley (mirror).
Mount crankshaft turning socket on crankshaft pulley 4 center torx bolts (mirror).
Mount ratchet on crankshaft turning socket (1/2″ long-arm ratchet).
If manual transmission, place transmission in neutral. This allows turning of crankshaft.
Turn crankshaft pulley clockwise until cylinder 1 intake and exhaust cams point to each other at ~45 degree angle (crankshaft turning socket / 1/2″ long-arm ratchet).
Note: Turning crankshaft counter clockwise is acceptable.
To begin , inspect the TDC (top dead center) timing marks on the engine timing cover and the crankshaft harmonic balancer, which are located at approximately the 11 o’clock position. For better visibility , use a mirror to clearly see the marks.
Following that , adjust the crankshaft pulley to align the TDC timing marks using a crankshaft turning socket and a 1/2″ long-arm ratchet.
As a final check , ensure that the pointer on the timing cover is precisely aligned with the single mark on the harmonic balancer, as this alignment is crucial for achieving accurate timing.
Note: If timing cover timing mark not visible clean timing cover to show timing mark (brake cleaner & towels).
Note: If timing marks on harmonic balancer not visible they might be hidden behind water pump pulley. Turn crankshaft pulley counter clockwise.
Note: Precise alignment is not necessary.
To start , detach the vanos electrical connectors cover by removing the two mounting nuts using a 10mm socket and a 3/8″ ratchet.
Once the nuts are removed , proceed carefully to lift off the cover, ensuring it is done gently to avoid any damage.
Note that this process applies specifically to the Euro S50 Single Vanos system.
First , disconnect the two electrical cable connectors for the vanos solenoid.
To do this , press in the connector wire clip and then pull off the connector carefully.
First , remove the two solenoid electrical cable connectors from their mounting brackets.
Then , carefully pull the connectors out of the brackets to fully detach them.
To prepare , insert a double-length, double-layer towel under the vanos unit, ensuring it rests securely on the thermostat and radiator lower hose.
This will help protect the surrounding components and absorb any potential spills during the process.
First , remove the vanos oil accumulator pipe from the vanos unit.
Next , use a 12mm open wrench to remove the oil pipe mounting bolt.
Once the bolt is removed , pull out the oil pipe from the vanos and position it above the vanos, as shown in the next picture.
First , slightly loosen the vanos oil pressure restrictor using a 22mm open wrench.
Note that the work on the pressure restrictor will be performed at the bench, as this step is only preliminary.
Loosening is easier to perform while vanos is mounted.
To begin , detach the vanos solenoid cover, which is specific to the Euro S50 Single Vanos system.
Next , using a 4mm hex bit socket with a 3/8″ ratchet, remove the four mounting bolts securing the cover.
Take off the cover and then peel away the cover paper gasket.
Pry the upper solenoid out of the Vanos body.
To begin, carefully position your tool to pry the solenoid. Next, leverage against the Vanos body and gently pry the solenoid out from the mid-body groove using a medium-head flathead screwdriver.
Attempts from multiple positions might be needed to remove the solenoid.
In some cases, you may need to try prying from different angles or positions to successfully remove the solenoid. Be patient and avoid using excessive force to prevent damage.
Note: Do not leverage against the solenoid circuit board, as it can be damaged.
Always remember to avoid placing pressure on the solenoid’s circuit board during removal. Instead, focus your leverage on the Vanos body to ensure the solenoid is removed safely.
Remove the solenoid from the Vanos.
Once the solenoid is loosened, carefully lift it out of the Vanos body. Ensure that all connections are clear and that no components are damaged during the process.
Next , pry the lower solenoid out of the vanos body by leveraging against the vanos body itself.
To accomplish this , use a medium-head flathead screwdriver to carefully pry the solenoid out from the mid-body groove.
If needed , attempt this from multiple positions, as it may take several tries to fully remove the solenoid.
However , ensure that you do not leverage against the solenoid circuit board, as it is sensitive and can be damaged.
Finally , once the solenoid is loosened, remove it completely from the vanos.
Insert towels in vanos solenoid chambers to protect oil passages from debris contamination (towels).
When inspecting the alignment , the groove on the exhaust camshaft at the first guide bearing will be roughly aligned with the groove on the first bearing cover, as shown in the picture.
This alignment serves as a key reference point during reassembly or inspection.
To begin , fully retard the intake camshaft timing by placing an open wrench (24mm combo wrench) on the hex at the front of the intake camshaft.
Next , rotate the intake camshaft counterclockwise until it reaches its adjustment end position.
This step ensures the camshaft is properly aligned for timing adjustments.
If camshaft resistant to rotation rock camshaft back and forth to release seize.
Note: Rotating camshaft is most effective when standing at exhaust side of car.
Camshaft groove on first guide bearing will be roughly aligned with groove on first bearing cover (picture).
Note (Euro S50 Single Vanos):
When working with the Euro S50 Single Vanos system, it’s important to understand that camshaft adjustment causes full camshaft timing retard. As a result, the splined shaft and Vanos piston move into a forward position. This positioning is intentional and facilitates access for disconnecting the splined shaft from the Vanos piston in the coming step.
Remove the Vanos intake cylinder cover bolts.
Begin by locating the bolts on the Vanos intake cylinder cover. Then, use the appropriate tools to carefully remove them.
Remove the cover’s 6 mounting bolts.
To do this, use a 4mm hex bit socket with a 3/8″ drive and a 3/8″ ratchet. Once the bolts are loosened, set them aside in a safe place to avoid losing them.
Note: If bolt not removed previously, paint drop will be found at bolt head base and cover. This is used in car assembly to verify bolt is fully tightened with toque wrench.
Remove the intake cylinder cover.
Start by ensuring the mounting bolts have been fully removed. Then, carefully pry the cover at multiple locations to remove it evenly. For this step, use a small putty knife to avoid damaging the cover or surrounding components.
Note: Orient the blade with the edge ramp side to the Vanos body.
When prying, make sure the blade is oriented with the edge ramp side facing the Vanos body. This orientation is more effective and helps prevent damage to the cover or Vanos body.
Note: Cover resistance is due to the cover sealing O-ring.
Keep in mind that the resistance you feel is caused by the cover’s sealing O-ring. To avoid damaging the O-ring or cover, apply even pressure and work slowly when prying.
Remove vanos intake piston mounting nut.
Initially loosen nut by counter holding splined shaft stud and unscrewing nut (7mm box wrench, 4mm socket (6-point) 1/4″ / 1/4″ ratchet).
Once nut is loosened, unscrew nut by counter holding nut and screwing splined shaft stud (7mm box wrench, 4mm socket (6 point) 1/4″ / 1/4″ ratchet).
When nut is close to end of shaft and shaft can no longer be held with tool, counter hold piston/shaft by hand and unscrew nut (fingers, 7mm box wrench).
Memo:
It is critical to use a 6-point socket, as a 12-point socket is susceptible to stripping the shaft hex. Always ensure you have the correct tools before starting the procedure.
Note (Euro S50 Single Vanos):
Additionally, be sure to use the box end of a wrench, as an open wrench is susceptible to stripping the nut hex. This precaution will help avoid damage to the components during removal.
Detach the TDC sensor in the Vanos bridge.
First, locate the TDC sensor on the Vanos bridge. Then, using a 5mm hex bit socket with a 3/8″ ratchet, remove the three mounting bolts securing the sensor plate.
Carefully lift the sensor plate along with the sensor and set it aside.
Once the bolts are removed, gently lift the sensor plate and the attached sensor. Make sure to handle them carefully and set them aside in a safe location to avoid damage.
Next, detach the nine Vanos mounting bolts—five on the upper section and four on the lower—using the same 5mm hex bit socket and 3/8″ ratchet.
Begin by identifying the nine mounting bolts, ensuring you note the five on the upper section and the four on the lower section. Then, using the 5mm hex bit socket and 3/8″ ratchet, carefully remove each bolt. Take care to keep track of their locations, as they may vary in size and threading.
Note: Upper right and left end bolts are long. The right bolt is fully threaded, and the left bolt is partially threaded.
Specifically, the upper right and left end bolts are longer than the others. Additionally, the right bolt is fully threaded, while the left bolt is only partially threaded. Keep this in mind when removing and reinstalling them to ensure proper alignment and fit.
Note: Lower second bolt from right also mounts vanos ground wire.
Remove the Vanos bridge bolts.
Start by locating the four mounting bolts on the Vanos bridge. Then, prepare your tools for removal.
Remove the Vanos bridge’s 4 mounting bolts using a 6mm hex bit socket with a 3/8″ long-arm ratchet.
Carefully remove each bolt, ensuring you keep track of their positions. Take note that the center two bolts are long, while the outer two bolts are short.
Note: The center 2 bolts are long, and the outer 2 bolts are short.
Specifically, the center bolts are longer in length, while the outer bolts are shorter. Be sure to organize them accordingly to avoid confusion during reinstallation.
Remove vanos bridge.
Wiggle vanos bridge while pulling up to remove vanos bridge from engine head.
Note: Gasket sealant at base of bridge acts as adhesive mounting bridge to engine head. Wiggling bridge helps break sealant bond.
Caution: When removing vanos, exhaust oil pump driver must be held in place on vanos then removed. Otherwise driver will fall in oil pan.
Probing vanos forward off engine head while holding exhaust oil pump driver on vanos.
Pry between vanos and engine head at vanos top right and left ends (medium putty-knife).
Pry vanos evenly rotating between each side until vanos releases and separates from engine head.
Note: Vanos resistance is due to vanos intake and exhaust head sealing O-rings.
To proceed , pull the vanos forward off the engine head and remove the exhaust oil pump driver.
Note that , once the vanos comes off the engine head, it will be suspended on the intake splined shaft.
However , exercise caution when working with the Euro S50 Single Vanos system: once the vanos is pulled off the engine head, it should not be remounted without first installing and aligning the exhaust side vanos oil pump driver.
This is critical , as a misalignment combined with pressure from the vanos mounting bolts can lead to breakage of the vanos bridge.
To begin , remove the vanos from the engine head by carefully lifting the vanos intake piston off the intake splined shaft stud.
Next , lift up the vanos slightly, then wiggle and pull it forward to fully remove the vanos intake piston from the splined shaft stud.
As a reminder , the splined shaft stud inserted into the piston has an O-ring at its center, which mates with the inner diameter of the piston.
Resistance to removal is due to this O-ring.
Take vanos to work bench.
Clean outside of vanos to remove dirt and sludge (brake cleaner & towels).
Installation of vanos seals
During following seals installation procedure, great care should be taken to not drop and damage vanos components. Perform work over table, so if part is dropped it will fall to table top.
Note that it is important to try not to disturb the vanos oil pump’s rotational position, as it is currently aligned to mate with the exhaust camshaft oil pump driver.
With this in mind , proceed carefully when installing the vanos intake seals for the Euro S50 Single Vanos system.
To begin , remove the intake piston from the intake cylinder by pressing it from the vanos inboard side.
Then , continue applying pressure to push it out through the vanos outboard side, which can be easily done using your finger.
First , detach the intake cylinder cover from the vanos inboard side.
Then , remove the five mounting bolts using a 4mm hex bit socket with a 3/8″ ratchet.
To begin , remove the intake cylinder cover by prying it at multiple locations to evenly lift it off. For this step , use a small putty-knife to ensure even pressure.
As you proceed , carefully orient the blade with the edge ramp side facing the vanos body, since this orientation is more effective for removing the cover without causing damage.
Note: Cover resistance is due to cover sealing O-ring.
Remove intake cover washer (fingers).
To begin , remove the intake cylinder from the vanos housing by pressing it from the vanos inboard side to push it out through the vanos outboard side.
For this step , use a 24mm 1/2″ socket to apply even pressure and ensure smooth removal.
If cylinder resistant, hit press tool to knock out cylinder (1/2″ ratchet head side).
First , remove the intake cylinder sealing O-ring by prying it out of the cylinder groove using a hook pick.
Once the O-ring is removed , clean the intake cylinder thoroughly using brake cleaner and towels.
Next , clean the intake cylinder vanos housing with brake cleaner and towels to ensure all components are free of debris and residue.
To begin , install the new O-ring on the intake cylinder by inserting one end of the O-ring into the cylinder groove and stretching the other end over the cylinder, then gently dropping it into place (use your fingers for this step).
Once the O-ring is in position , lightly lubricate it with assembly oil to ease the cylinder installation process.
As a reminder , the intake cylinder O-ring is one of two identical O-rings; the second identical O-ring is used for the intake inboard cover.
First, lightly lubricate the intake cylinder Vanos housing with assembly oil to ease the cylinder installation process.
This step ensures smoother movement and reduces friction during installation.
Next, insert the intake cylinder into the Vanos housing from the Vanos outboard side.
As you do this, make sure to handle the cylinder carefully to avoid misalignment or damage.
Once inserted, rotate the cylinder within the Vanos to align the cylinder cutouts with the Vanos housing oil access holes located at the sides of the Vanos cylinder housing.
During this process, take your time to ensure the cutouts and oil access holes are perfectly aligned. Proper alignment is crucial for the Vanos system to function correctly.
Finally , turn the vanos inboard side down to keep the cylinder securely in place within the housing.
First , remove the intake cylinder outboard cover sealing O-ring by prying it from the cover groove using a hook pick.
Once the O-ring is removed , clean the intake cylinder cover thoroughly using brake cleaner and towels, especially for the Euro S50 Single Vanos system.
Note: Do not install new cover O-ring at this time. Cover will be easier to install and remove in next step without cover O-ring.
Install and then remove intake cylinder outboard cover.
Align the cover bolt holes to the Vanos body bolt holes.
Start by positioning the cover carefully to ensure the bolt holes match up perfectly. This alignment is essential for proper installation.
Install the cover’s 6 mounting bolts using a 4mm hex bit socket with a 3/8″ drive.
As you install the bolts, make sure they are threaded correctly to avoid cross-threading.
Tighten the bolts evenly in multiple passes.
To ensure even pressure, tighten the bolts gradually, alternating between them in a crisscross pattern. This method prevents warping or misalignment of the cover.
Note: Tightening the cover bolts presses the intake cylinder into the Vanos housing.
Keep in mind that this step secures the intake cylinder in place, so ensure the bolts are tightened properly.
Remove the cover’s 6 mounting bolts using a 4mm hex bit socket with a 3/8″ drive.
Once the bolts are loosened, carefully set them aside in a safe place to avoid losing them.
Remove the cylinder cover.
After removing the bolts, gently lift the cover away from the Vanos housing. Be careful not to damage any surrounding components during this process.
To begin , install the new O-ring on the intake cylinder cover by inserting one end of the O-ring into the cover groove and stretching the other end over the cover, then gently dropping it into place (use your fingers for this step).
Once the O-ring is in position , lightly lubricate it with assembly oil to ease the cover installation process.
As a helpful note , the intake cylinder cover O-ring is the larger of the three remaining similar O-rings that fit the cover, so ensure you select the correct one before proceeding.
To begin , remove the intake rod seal from the intake inboard cylinder cover by prying it out from the cover’s outboard side to push it through to the inboard side.
For this step , use a straight pick, especially when working on the Euro S50 Single Vanos system, to carefully and effectively remove the seal.
Remove intake cylinder inboard cover sealing O-ring.
Begin by prying the O-ring from the cover groove, and then remove it from the cover using a hook pick.
Next, clean the intake cylinder inboard cover thoroughly using brake cleaner and towels.
Remove the intake cylinder inboard cover sealing O-ring.
To start, carefully pry the O-ring from the cover groove using a hook pick, and then remove it completely from the cover.
Afterward, proceed to clean the intake cylinder inboard cover thoroughly using brake cleaner and towels.
Install the new intake rod seal into the intake cylinder inboard cover.
First, insert the seal into the housing on one side, and then press it into the housing on the opposite side.
Once the seal is partially inserted into the housing, press it fully into place along its perimeter using your thumb. At this point, the seal should be fully seated in the housing (refer to the picture for guidance).
Finally, press the O-ring into the rod seal to verify that the O-ring is fully inserted.
Disconnect intake piston end cap from main piston body (hands, Euro S50 Single Vanos).
Remove intake piston seal from intake piston cap.
Pry piston seal from piston cap (small putty-knife).
Note: Orient putty-knife with edge ramp side to piston cap wall. This orientation is more effective.
Remove paper gasket from intake piston or piston cap.
Pry off and scrape off paper gasket as necessary from piston or piston cap (strait pick).
Fully remove all paper gasket.
Note: Paper gasket excessively widens piston seal groove allowing seal to tilt in groove and wear unevenly. Gasket only seems to function to better seat piston cap before mounting. This is not needed.
Install new piston seal rubber ring on piston cap shaft (fingers).
Fully insert rubber ring onto piston cap (fingers).
Stretch intake piston new Teflon ring.
Place Teflon ring on piston shaft and pick tool on Teflon ring (90 degree pick) (picture).
Leverage pick tool against piston and tilt pick tool to stretch out Teflon ring (90 degree pick).
Perform Teflon ring stretching at multiple locations along Teflon ring until Teflon ring notably stretches.
Note: Teflon ring needs to stretch sufficiently to install over piston seal rubber ring in next step.
Note: Multiple attempts can be made of stretching Teflon ring and attempting next step install.
Install piston seal Teflon ring onto piston seal rubber ring.
If Teflon ring is too small, repeat previous Teflon ring stretching step.
Continue stretching and attempting to install Teflon ring until it installs.
Do not over stretch Teflon ring. Stretch only sufficiently to install.
Fully insert Teflon ring onto rubber ring.
Mount intake piston cap onto intake piston. (Euro S50 Single Vanos)
Insert intake piston seal end into intake cylinder outboard side.
Lightly lubricate cylinder entry inner wall and piston Teflon ring (assembly oil).
Wiggle piston and press strait into cylinder.
Verify Teflon ring is inserting into cylinder at all perimeter locations. Reposition piston and reattempt insertion to facilitate Teflon ring full perimeter insertion.
Once all Teflon ring perimeter inserts into cylinder, wiggle piston and press strait into cylinder to fully insert Teflon ring into cylinder.
Note: Cylinder entry has chamfer which allows for stretched Teflon ring to be collected and inserted into cylinder.
Maintain piston in cylinder for 1 minute then remove.
This period allows Teflon ring to be compressed (resized) close to original size.
Remove piston from cylinder.
Note Teflon ring has decreased in diameter.
Remove piston cap from piston.
Place piston cap, shaft first, into intake cylinder outboard end.
Insert piston cap into cylinder by pressing with piston cap end.
Press cap ~1/3 down cylinder.
Place intake piston vertically with cap end down. (Euro S50 Single Vanos)
Slide intake cylinder cover washer onto piston.
Insert intake cylinder cover with new rod seal onto piston.
Lightly lubricate piston and rod seal inner Teflon lip (assembly oil, Euro S50 Single Vanos).
Press cover strait onto piston without tilting.
Press cover over piston until ~10mm of piston is protruding from cover (next picture).
Clean vanos intake cylinder inboard side cover mating surfaces and cover mounting bolts (brake cleaner & towels).
Insert intake piston, cap end first, into intake cylinder inboard side.
Slide cylinder cover washer up to cover.
Insert piston into cylinder.
Mount piston to piston cap by pressing on piston and piston cap from both ends of cylinder (finger, hand).
Mount intake cylinder cover washer onto cylinder.
Fully seat washer.
Mount intake cylinder cover onto vanos body.
Rotate cover/piston to align cover holes with vanos body holes (picture).
Brace piston from vanos outboard side (finger) and press cover down piston and onto vanos body.
Rotate cover/piston to align cover holes with vanos body holes (picture).
Press cover onto vanos body.
If present, cover alignment small pin hole will insert onto vanos body alignment pin.
Install intake cover 5 mounting bolts (4mm hex bit socket 3/8″ / 3/8″ ratchet).
Tighten bolts evenly to draw cover evenly to vanos body.
Note: If top end of cover not inserting hit with object to insert (ratchet handle)
Fully tighten, 6 Nm (4.5 ft-lb) (4mm hex bit socket 3/8″ / 3/8″ torque wrench).
Note: Tighten bolts evenly in multiple passes. Verify one pass with all bolts fully tightened.
Installation of vanos oil pump cover O-rings
Detach vanos oil pump cover from vanos outboard side.
Remove cover 8 mounting bolts (4mm hex bit socket 3/8″ / 3/8″ ratchet).
Remove oil pump cover.
Insert blade between vanos body and cover to lift cover at perimeter (small putty-knife & hammer).
Initially insert blade at best access location (picture).
Note: Orient blade with edge ramp side to vanos body. This orientation is more effective.
Once cover is lifted at perimeter, pry cover at multiple locations to evenly remove cover (small putty-knife).
Note: Cover resistance is due to cover sealing O-ring.
Remove oil pump cover oil feed sealing O-ring.
Pry O-ring from face groove and remove from vanos (hook pick).
Clean O-ring face groove (brake cleaner & towels).
Install new O-ring on oil pump cover oil feed sealing face.
Insert new O-ring in face groove (fingers).
Note: Oil pump oil feed O-ring is similar in size to oil pressure restrictor small O-ring. Oil feed O-ring is slightly thicker in cross section than oil pressure restrictor small O-ring.
Note: Oil pump oil feed O-ring is one of two identical O-rings. Second identical O-ring is vanos inboard oil feed O-ring.
Remove oil pump cover sealing O-ring.
Pry O-ring from cover groove and remove from cover (hook pick).
Clean oil pump cover (brake cleaner & towels).
Install new O-ring on oil pump cover.
Insert O-ring in cover groove on one end and stretch other end over cover and drop into groove (fingers).
Lightly lubricate O-ring to ease cover installation (assembly oil).
Install oil pump cover on vanos.
Orient cover to align cover oil feed ridge with vanos oil feed hole (picture).
Align cover bolt holes to vanos body bolts holes.
Press cover onto vanos body.
Install oil pump cover 8 mounting bolts (4mm hex bit socket 3/8″ / 3/8″ ratchet).
Tighten bolts evenly to draw cover evenly to vanos body.
Fully tighten, 6 Nm (4.5 ft-lb) (4mm hex bit socket 3/8″ / 3/8″ torque wrench).
Note: Tighten bolts evenly in multiple passes. Verify one pass with all bolts fully tightened.
Remove vanos inboard intake head sealing O-ring.
Pry O-ring from housing groove and remove from vanos (hook pick).
Clean O-ring housing groove (brake cleaner & towels).
Install new O-ring on vanos inboard intake head sealing housing.
Insert new O-ring in housing groove on one end and stretch other end over housing and drop into groove (fingers).
Lightly lubricate O-ring to ease vanos installation (assembly oil).
Note: Inboard intake head sealing O-ring is one of two identical O-rings. Second identical O-ring is inboard exhaust head sealing O-ring.
Remove vanos inboard exhaust head sealing O-ring.
Pry O-ring from housing groove and remove from vanos (hook pick).
Clean O-ring housing groove (brake cleaner & towels).
Install new O-ring on vanos inboard exhaust head sealing housing.
Insert new O-ring in housing groove on one end and stretch other end over housing and drop into groove (fingers).
Lightly lubricate O-ring to ease vanos installation (assembly oil).
Remove vanos inboard oil feed head sealing O-ring.
Pry O-ring from face groove and remove from vanos (hook pick).
Clean O-ring face groove (brake cleaner & towels).
Install new O-ring on vanos inboard oil feed head sealing face.
Insert new O-ring in face groove (fingers).
Note: Inboard oil feed O-ring is similar in size to oil pressure restrictor small O-ring. Oil feed O-ring is slightly thicker in cross section than oil pressure restrictor small O-ring.
Unscrew oil pressure restrictor from vanos body (hand).
Drain and discard oil from vanos.
Clean restrictor and vanos restrictor area (brake cleaner & towels).
Cut cross section of small O-ring on pressure restrictor (razor knife).
Note: Rocking of blade while pressing helps create cutting motion.
Note: Take care to not cut or damage adjacent plastic washer. Plastic washer has cut cross section.
Remove cut O-ring from pressure restrictor.
Remove large O-ring from pressure restrictor (90 degree pick).
Clean pressure restrictor O-ring grooves (brake cleaner & towels).
Install new large O-ring on pressure restrictor. Roll O-ring onto pressure restrictor until O-ring drops into base groove.
Install small O-ring on pressure restrictor. Roll O-ring onto pressure restrictor until O-ring drops into groove.
Note: White washer should be positioned in groove on side of regulator large end (picture).
Lightly lubricate O-rings to ease pressure restrictor installation (assembly oil).
Screw pressure restrictor into vanos body (hand).
Note: Pressure restrictor will be tightened once vanos is mounted on engine.
Remove intake splined shaft stud O-ring.
Pry O-ring from stud groove and remove from stud (90 degree pick).
Clean splined shaft stud (brake cleaner & towels).
Note: If installing rattle kit, delay splined shaft O-ring installation until after rattle kit installation.
Install new O-ring on intake splined shaft stud.
Insert new O-ring on splined shaft stud and roll O-ring down stud and drop into groove (fingers).
Lightly lubricate O-ring to ease vanos installation (assembly oil).
For both solenoids, perform following O-rings removal and install.
Cut cross section of solenoid small and large O-rings (razor knife).
Note: Rocking of blade while pressing helps create cutting motion.
Note: Do not press into solenoid as this nicks sealing surface.
Rotate blade in O-ring after cutting to note any remaining uncut O-ring (razor knife).
Remove cut O-rings from solenoid.
Clean solenoid (brake cleaner & towels).
Install new small and large O-rings on solenoid (fingers).
O-rings should not be twisted in final position.
Lightly lubricate O-rings to ease solenoid installation (assembly oil).
Repeat O-rings removal and install for second solenoid.
Remove vanos oil filter and washer (5mm hex bit socket 3/8″ / 3/8″ ratchet).
Clean vanos outer face at oil filter hole (brake cleaner & towels).
Install vanos new oil filter and washer (5mm hex bit socket 3/8″ / 3/8″ ratchet).
Fully tighten, 12 Nm (9 ft-lb) (5mm hex bit socket 3/8″ / 3/8″ torque wrench).
Remove towels from vanos solenoid chambers.
Clean vanos solenoid chambers (brake cleaner & towels).
Clean vanos solenoid housing and cover matting surfaces (brake cleaner & towels).
Insert new clean towels in vanos solenoid chambers to protect oil passages from debris contamination (towels).
Perform rattle procedure
If performing rattle repair continue at this point with rattle procedure, Euro S50 Single Vanos Rattle Procedure
Cleaning of parts
Note: When cleaning parts, spray cleaning compound on towel then wipe component with towel. Components can also be placed in small container and sprayed with cleaning compound then individually wiped with towel.
Clean all mounting bolts, nuts, washers (brake cleaner & towels).
Clean vanos matting surfaces; solenoid cover and bolts, intake cylinder outboard housing and cover bolts, inboard face (brake cleaner & towels).
Note: Do not rotate vanos exhaust oil pump.
Thoroughly clean the polished surfaces of the vanos bridge, including the top gasket surface, arches, and base bottom, making sure to remove any old sealant (use brake cleaner and towels).
For the head matting surfaces, focus on cleaning the spark plug well, the top perimeter, the front half-moons, and the front polished areas (brake cleaner and towels will work best).
Wipe down both the vanos ground wire and the valve cover ground wire using brake cleaner and towels to ensure they’re free of dirt and residue.
Finally, clean the mounting contact surfaces of the coils (at the coil locations) with brake cleaner and towels to ensure proper electrical connections.
Remove valve cover gaskets from valve cover.
Clean valve cover gaskets (brake & towels). Note: Euro S50 valve cover gaskets are made of Viton and thus can withstand brake cleaner. Brake cleaner will allow for removing oil from gaskets.
Clean valve cover mating surfaces; inner gasket, bolt access holes, all studs (brake cleaner & towels).
Installation of vanos
Slightly advance intake camshaft position.
Rotate intake camshaft slightly clockwise (24mm open wrench).
Align intake timing grooves so camshaft bearing groove is slightly left of bearing cover groove (car rear orientation) (picture). If camshaft resistant to rotation rock camshaft back and forth to release seize.
Note: Rotating camshaft is most effective when standing at exhaust side of car.
Note: This step insures vanos intake piston/splined shaft stud do not protrude too far and obstruct mounting of vanos intake cylinder cover.
Inspect TDC (top dead center) timing marks on engine timing cover and crankshaft harmonic balancer at ~11 o’clock position (mirror).
If needed, adjust crankshaft pulley to align TDC timing marks (crankshaft turning socket / 1/2″ long-arm ratchet).
Note: Precise alignment is not necessary.
If crankshaft adjusted, double check and readjust camshafts timing as above.
After above camshaft adjustment, intake splined shaft will be slightly more recessed into sprocket (picture).
Move vanos ground wire forward and position end under vanos solenoid cable connector bracket.
Note: This allows installing vanos on engine head without ground wire being caught between vanos and engine head.
Verify vanos inboard side is clean and ready for installation.
As needed, wipe down vanos inboard surfaces (brake cleaner & towels).
Note: Do not rotate vanos exhaust oil pump.
Install vanos on engine head.
Insert vanos intake piston onto intake splined shaft stud.
Stop when resistance is met.
Install exhaust oil pump driver on vanos oil pump and rotate as needed to align with exhaust sprocket driver.
Hold driver in position while inserting vanos in next step.
Insert thumb into vanos intake cylinder and press on piston.
Lift up vanos. Wiggle and press vanos onto engine head.
Rotate vanos oil pump and driver as needed to align and insert driver into exhaust sprocket driver.
Note: Intake splined shaft stud O-ring will seize on piston inner walls and prevent insertion. Wiggling and pressing vanos helps release O-ring seize and facilitates vanos advance.
Note: When vanos advances, splined shaft stud will come through piston front center hole (picture).
Stop advancing vanos once splined shaft stud protrudes from vanos intake piston and oil pump driver mates with exhaust sprocket driver. Vanos should not be fully mounted.
Apply thin layer of sealant to vanos bridge bottom base surfaces.
Allow sealant to solidify for ~2 minutes before mounting bridge.
Install vanos bridge onto engine head.
Orient bridge with large arch on exhaust side (picture).
Insert bridge bottom side dowel holes (small) onto engine head dowels.
Fully seat bridge onto engine head.
Install vanos bridge 4 mounting bolts (6mm hex bit socket 3/8″ / 3/8″ ratchet).
Note: Center 2 bolts are long and outer 2 bolts are short.
Fully tighten, 10 Nm (7 ft-lb) (6mm hex bit socket 3/8″ / 3/8″ torque wrench).
Note: Tighten bolts evenly in multiple passes. Verify one pass with all bolts fully tightened.
Wipe excess sealant from vanos bridge base perimeter (finger).
Note: Engine head half-moons and vanos bridge arches combine to create cavities for vanos inboard intake and exhaust protrusions to insert into. Vanos intake and exhaust protrusion O-rings seal engine oil from leaking externally.
Place thumb on vanos intake piston to keep from falling out of cylinder.
Lift up vanos. Wiggle and press vanos onto engine head.
Note: Intake splined shaft stud O-ring will seize on piston inner walls and prevent insertion. Wiggling and pressing vanos helps release O-ring seize and facilitates vanos advance.
Note: When vanos advances, splined shaft stud will come through piston front center hole (picture).
Press vanos onto engine head until vanos O-rings reach head / bridge and resistance is encountered.
Note: Vanos O-rings will insert partially into head / bridge.
Initially thread vanos 9 mounting bolts, 5 upper and 4 lower.
Note: Upper right and left end bolts are long. Right bolt is fully threaded and left bolt is partially threaded.
Note: Lower second bolt from right mounts vanos ground wire.
Tighten vanos 9 mounting bolts (5mm hex bit socket 3/8″ / 3/8″ ratchet).
Tighten bolts evenly in multiple passes to draw vanos slowly and evenly to engine head and vanos bridge.
Vanos O-rings will insert into engine head and vanos bridge.
Vanos will fully mate with engine head.
Caution: This is a critical step. If vanos oil pump is not correctly aligned with exhaust camshaft drive damage can occur. Tighten bolts evenly and note any resistance to bolt tightening and vanos insertion. If bolts are tighter on exhaust side and vanos is not inserting, stop. Remove vanos from engine head and repeat procedure for vanos oil pump alignment.
Fully tighten vanos 9 mounting bolts, 8 Nm (6 ft-lb) (5mm hex bit socket 3/8″ / 3/8″ torque wrench).
Note: Tighten bolts evenly in multiple passes. Verify one pass with all bolts fully tightened.
Set up TDC sensor in vanos bridge.
Install sensor plate with sensor on bridge.
Install sensor plate 3 mounting bolts (5mm hex bit socket 3/8″ / 3/8″ ratchet).
Fully tighten plate 3 mounting bolts, 8 Nm (6 ft-lb) (5mm hex bit socket 3/8″ / 3/8″ torque wrench).
Note: Tighten bolts evenly in multiple passes. Verify one pass with all bolts fully tightened.
Press on vanos intake piston end cap at multiple locations to fully seat cap on piston.
Clean piston cap and splined shaft stud (brake cleaner & towels).
Initially install vanos intake piston / splined shaft new mounting nut.
Screw nut on splined shaft stud (fingers).
Counter hold piston/shaft by hand and screw nut (fingers, 7mm box wrench).
Note: Nut can only be slightly installed on shaft. This allows slight section of shaft stud to protrude from nut and allow counter holding shaft in next step.
Fully mount nut by counter holding shaft stud and screwing on nut (4mm socket (6 point) 1/4″ / 1/4″ ratchet, 7mm open wrench).
Note: At first, shaft tool (4mm socket) will only barely mount on splined shaft end.
Fully tighten nut, 9 Nm (6.5 ft-lb) (7mm box wrench, 4mm socket (6 point) 1/4″ w/ 3/8″ to 1/4″ socket adapter / 3/8″ torque wrench).
Message: It is critical 6-point socket be used, as 12-point socket is susceptible to stripping shaft hex.
Note: Be sure to use wrench box end, as open wrench is susceptible to stripping nut hex.
Note: Intake piston end is recessed slightly into intake cylinder. This is due to slight advance (clockwise) adjustment of intake camshaft. This assures piston / splined shaft stud do not interfere with cylinder cover installation.
Install vanos intake cylinder cover.
Orient cover with side slight indent to vanos oil filter cap (picture right).
Press cover onto vanos body.
Install vanos intake cover 6 mounting bolts (4mm hex bit socket 3/8″ / 3/8″ ratchet).
Tighten bolts evenly to draw cover evenly to vanos body.
Fully tighten, 5 Nm (4 ft-lb) (4mm hex bit socket 3/8″ / 3/8″ torque wrench).
Note: Tighten bolts evenly in multiple passes. Verify one pass with all bolts fully tightened.
Verification of engine timing
If rattle kit was installed, perform verification of engine timing procedure in rattle procedure.
Euro S50 Single Vanos Rattle Procedure
Installation of solenoids
Remove towel from vanos solenoid chambers.
Insert vanos top and bottom solenoids into solenoid chambers.
Note: Top solenoid has long cable and bottom solenoid has short cable.
Rotate solenoids to align cable grommet with housing groove.
Insert cable grommets into housing grooves.
Press solenoids to insert fully into chambers.
Rotate solenoids if necessary to align further.
Press on solenoids to verify full insertion.
Apply multiple thin dots of sealant along solenoid cover matting surface (sealant / finger).
Place solenoid cover gasket on solenoid cover matting surface.
Align gasket with housing surface and bolt holes.
Press gasket to bind with sealant and hold on housing surface.
Mount solenoid cover and 4 mounting bolts.
Some alignment of bolts with cover gasket might be necessary.
Initially tighten solenoid cover 4 bolts (4mm hex bit socket / hand).
Fully tighten, 8 Nm (6 ft-lb) (4mm hex bit socket 3/8″ / 3/8″ torque wrench).
Note: Tighten bolts evenly in multiple passes. Verify one pass with all bolts fully tightened.
Insert solenoid electrical cable connectors into connector brackets under vanos.
Note: Connectors are keyed with brackets and will only insert in one orientation.
Connect vanos electrical cable connectors to vanos solenoid cable connectors in connector brackets.
Note: Orient right connector metal clip down and left connector metal clip out.
Press in connectors until wire clip snaps into place.
Install vanos electrical connectors cover.
Align and install cover on connector bracket studs.
Mount cover 2 nuts (10mm socket 3/8″ / 3/8″ ratchet).
Lightly tighten.
Fully tighten vanos oil pressure restrictor, ~14 Nm (by feel) (22mm open wrench).
Install vanos oil accumulator pipe.
Pull oil pipe to side and inset into vanos oil pipe hole.
Screw on oil pipe mounting bolt (12mm open wrench).
Fully tighten, 20 Nm (by feel) (12mm open wrench).
Installation of valve cover
Mount valve cover perimeter gasket and sparkplug well gaskets on engine head.
Orient sparkplug well gaskets with end bolt hole to front (picture) and perimeter ridges down.
Install valve cover on engine head.
Align valve cover with engine head and gaskets and lay valve cover on engine head.
Adjust valve cover perimeter gasket so each valve cover gasket bolt hole aligns with associate valve cover perimeter bolt hole.
Install valve cover 20 mounting bolts, 16 perimeter and 4 center (10mm socket 3/8″ / 3/8″ ratchet & extension).
Note: Front center (vanos bridge) bolt and 4 center bolts are short.
Note: Rear center bolt has limited access (10mm socket 3/8″ / 1/2″ ratchet & 1/2″ to 3/8″ socket adapter (extension)).
Tighten bolts evenly working back and forth, assuring even pressure distribution on cover. Tighten until bolts bottom out on head.
Fully tighten, 8Nm (6 ft-lb) (10mm socket 3/8″ / 3/8″ torque wrench & extension).
Install valve cover ground wire w/ nut on valve cover rear most stud (picture) (10mm socket 3/8″ / 3/8″ ratchet).
Install each coil into original sparkplug well and mount with 2 nuts (10mm socket 3/8″ / 3/8″ ratchet & extension). Rotate between coil mounting nuts to mount coil evenly.
Note: Coil boot will not fully insert onto sparkplug during initial mount. This is normal.
Fully tighten, 10Nm (7 ft-lb) (10mm socket 3/8″ / 3/8″ torque wrench & extension).
Rotate coils cables/bracket/boot back onto valve cover.
Mount coil cables rear boot rubber block onto valve cover. Slide rubber block onto valve cover slot from top (picture).
Set up coil cables mounting bracket.
Mount the bracket onto the two mounting studs. Secure the bracket by tightening the two mounting nuts using a 10mm socket, 3/8″ ratchet, and extension.
Attach the electrical connectors to the coil cables.
For each coil, lift up on connector metal lock, press in cable electrical connector, and push down on connector metal lock.
Route coil cables as needed.
Install engine top cover.
Align engine cover and place over valve cover.
Cover rear left will mount over coil cables boot rubber block. Press down on cover rear to fully mount block.
Install cover 4 mounting bolts (5mm hex bit socket 3/8″ / 3/8″ ratchet).
Installation of fan & shroud
Euro E36 M3 fan & shroud installation
Post repair procedures
Allow sealant to dry a minimum of one hour before driving car.
Check and replenish engine oil.
Drive car, then park car and let engine oil settle.
Remove oil dipstick; wipe dipstick end; fully reinsert dipstick; remove dipstick again; read oil marking. If oil is low add needed (small) amount of new oil at oil fill cap at valve cover.
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