This is a "how to" regarding valve adjustment and spark plug replacement on a BMW E85 / Z4 M with the S54 engine. While there is a lot of DIY's on how to do this on E46 M3 - there are some subtle disassembly differences between the two vehicles. I have never seen anyone do a comprehensive DIY on the Z4 M of the the valve adjustment procedure. The small Z4 M community always has to refer to the M3 procedure.
My purpose in doing this is to assemble comprehensive documentation of this procedure on a Z4 M from start to finish. I want to make this DIY so comprehensive - that almost anyone at home can do it. My attempt here is to think of ALMOST anything that could go wrong - and how to avoid it. Also, I would like to assemble a large compendium of information in one place regarding this procedure and the items needed to complete it.
I'd like to give a few words of advice about working on your own car. I've been fixing cars both professionally and at home for 25 years (no longer in the field). Nothing is more frustrating then breaking something, loosing something, or not having what you need on hand to complete the job. Take your time. Plan for multiple days to do more complicated work. Do not rush.
Breaking parts, connectors, wires, etc... can be an aggravating or costly (but mostly avoidable) disaster. Loosing bolts, breaking plastic rivets, or stripping threads means usually "rigging" up some fix that may not appear or work as the factory originally intended - or costing you more money and down time of your vehicle. Most of these "disasters", in my experience, can be avoided by taking your time, thinking things out, and treating everything like a fragile/costly and easily breakable part.
A job like this could likely be completed in 3-4 hours. I took my time, planned ahead, and purchased everything I could possibly need - and took about 8 hours over 2 days to do this job. While this is very slow work (I was also taking pictures and documenting for this article) - not a single connector, rivet, bolt, etc... was stripped, broken, or lost. It's my car - so I want it to be perfect and don't want any headaches in the process. Since I took my time - I know everything was done right and had no issues.
****Some Background
Valves open and close to let fuel into the engine and spent exhaust gasses out. Most vehicles today have hydraulic valve lifters that do not require adjustment. The S54 has solid lifters - therefore they require periodic adjustment. BMW recommends adjusting the valve clearances during every Inspection I & II. When exactly these inspections are required will vary based on the vehicle - as they are determined by the gallons of fuel the vehicle uses. Each inspection usually will fall somewhere between 20-30k miles.
Why do you have to adjust valves? Valve lash/clearance (the "play" or distance between the cam shaft and the rocker arm on S54) is critical for a number of reasons. If the valve is "too tight" (not enough lash) the valve will not seat on the valve seat for long enough - possibly causing the valve to burn (exhaust valves more likely here) and wear quickly . If the valves are "too loose" (too much lash) the engine will not "breath well" and poor performance and fuel economy will result. The valve train will also be noisy and excessive valve train wear will occur. Both situations can mean your engine will wear faster and run poorly.
How do you adjust valve "lash" or clearance on the S54? Valve clearance is adjusted on the S54 by replacing variable size "shims"/"pucks"/tappets between the valve tip and the rocker arm. For continuity sake - I will just call these "shims" from now on. All the valves come from the factory with a shim between the valve and the rocker arm. You are not determining if a shim is needed or not - but WHAT shim is needed - if the valves are out of spec. Any shim removed can be reused (assuming it's not burnt or damaged) if it's the correct thickness for another valve.
****Some Special Things You Need to Accomplish This Job
1. Drei Bond 1209/generic RTV:
Drei Bond 1209 is the RTV (room temperature vulcanizing) non solvent type silicone based sealant BMW recommends for the 2 half moon cutouts in the back of the head and the area where the head meets the VANOS (specifics on this later). This sealant is used between the head surface and the valve cover. "Drei" means "three" in German - so sometimes this product is referred to as Three/3 Bond 1209. The problem is - this stuff seems to be no longer available from BMW. In doing a little research on this product I found that it may or may not actually be available from BMW in The USA... However, Porsche also recommends this product and it's available from multiple Porsche websites. I believe the Porsche part number is: 000-043-203-73
An alternate RTV I've seen quoted was 3M 8661 and Loctite 80036/(PX66BR). For whatever reason, the Loctite number seems to bring up a valve grinding compound when you Google it. The 3M product doesn't look particularly appetizing to me - as it says you can use it on wood and all kinds of junk. So, since an RTV like product will be needed to do this job - I'd recommend just getting what is printed in BMW TIS - Drei Bond 1209.
Of course, Drei Bond 1209 cost a boat load of money (~ $30-$40 an ounce), compared to a tube of Permatex RTV from Pep Boys (~ $7 for multiple ounces). Will it make a difference wether you use Drei Bond 1209 or Permatex? Maybe so - maybe not. But, if going the Pep Boys/Permatex route, I'd recommend the best spec'ed RTV they have.
Some specs on Drei Bond 1209:
*1209 Non-solvent type silicone-based
-Offers the most excellent heat resistance among silicone-based sealants.
-Contains very little volatile low molecular siloxane (less than 0.03%).
-Does not corrode copper and copperbased alloys.
-Temperature resistant up to 200° C (~ 390° F).
2. Multiple cans of Brake Kleen (or generic):
I'm just going to call all brake cleaning products Brake Kleen - because that is just what I call it. I can tell you this stuff is almost a necessity to clean oil 100% off gasket mating surfaces so they are contaminate free before re-assembling. Oil on the gasket / gasket surface may mean your RTV may not cure correctly or your gasket may leak. So, in my book, this is an important step. Brake Kleen is so useful because it quickly removes most/all oil and grease and leaves no residue (vaporizes/flashes off 100%). That being said, a single can doesn't seem to go very far for me at least - so I always keep several.
Brake Kleen comes in two common types: chlorinated and non-chlorinated. If you happen to be in the state of California, I believe your only choice is the non-chlorinated type if sourced within state legally. It's my opinion that the chlorinated stuff just works better. However, do not use the chlorinated stuff around welding or anything hot that will cause the chlorinated Brake Kleen to rapidly give off vapors creating *PHOSGENE GAS*. Phosgene gas was used by various participants of WWI as a poisonous gas / weapon of war ("poison gas"). So, do not use this stuff in closed doors, around heat, and do not breath this stuff in.
Chlorinated Brake Kleen has also been shown to be carcinogenic (banned in CA) and can damage certain plastics and possibly paint. It is also flammable, whereas non-chlorinated Brake Kleen isn't as flammable (still flammable) - and is kinder to plastics/paint. While chlorinated Brake Kleen is worse for your health and worse for the environment - I'll still grab it over the non-chlorinated stuff every time. I don't use it much, breath it in, spray it in my mouth and eyes, or spray it on my paint.
3. Micrometer:
A micrometer is necessary to measure the thickness of the valve shim you take out - so you can figure out what size shim you need to put in. The micrometer I'm using is the 0-1" Mechanical Micrometer from Harbor Freight Tools. While Harbor Freight isn't known for their precision tool manufacturing, I did a little research on this micrometer and it actually tests quite accurate. Cost is about $22. I would not recommend using a micrometer bigger than 1" for this job.
The HF micrometer is sold as being accurate to 0.0001" (that's one TEN thousandths of an inch - or one piece of an inch broken up into ten thousand parts). I wouldn't spend too much on a micrometer. Units like this are considered accurate to 1/10,000". The clearance that needs to be measured here is 1/1000" (one ONE thousandths of an inch) - so most micrometers in the 1" range should be accurate enough. Another nice thing about this unit is it comes with an analogue reading display on the side. The micrometer zeroed out perfectly right out of the box for me. But it does include a little wrench in the case to adjust it if need be.
BMW actually specs the valve clearances in metric. It's easy enough to flip flop back and forth using an inch to millimeter converter which is easy enough to find on Google. I am choosing to do my measurements in standard opposed to metric. The reason for this is the micrometer I choose reads in standard measurement. While places like Harbor Freight do sell micrometers that have digital read outs on the side in standard AND metric - the actual barrel readings can only be calibrated one way. I prefer to check both readings to make sure the tool is consistent. I do not like relying on digital read outs for work like this. I found it a bit difficult to locally source a true metric barrel reading micrometer at the cost of this unit. However, for the easily confused - it may be worth ordering one online or just picking up one with a digital readout that can convert to metric for simplicity sake.
4. Feeler Gauges:
I would recommend getting a set of "bent" or angled feeler gauges. These are just easier to get between the cam and the rocker arm to measure valve clearance. However, you likely want to find a set that has all the feeler gauges between the range of the valve clearance specifications and then some. Intake spec is 0.007" - 0.009" (0.18-0.23 mm). Exhaust spec is 0.011" - 0.013" (0.28mm - 0.33mm). So, in my opinion, a set that has ALL the numbers from at least 0.005" - 0.015" is a good bet. Surprisingly, most feeler gauge sets do not have all the consecutive numbers in that range. They may not even have your target numbers (0.008" & 0.012"). However, a bent/angled set that does isn't too hard to find.
Most (if not all) feeler gauges have both metric and standard readings stamped on them. So, this usually isn't an issue. The set I decided to go with was easily sourced locally at Pep Boys. It's OEM brand tools #25349 Offset Feeler Gauge 16 Blades. It contains all feeler gauges from 0.005" (0.13 mm) to 0.020" (0.51 mm) - all the sizes you will need. I think it cost about $7.
5. Torque Wrench:
This may be optional - depending on your opinion. I've replaced valve cover gaskets on BMW inline 6 engines multiple times before and have never used a torque wrench. For those that may not know, a torque wrench is a tool to tighten a bolt to a specific torque or "tightness". There are manufacturer specs for the torque of the valve cover bolts ( ~ 8 ft/lbs * 10mm bolts), spark plugs (~ 20 ft lbs), and the banjo oil bolt (18 ft lbs * 17mm bolt) on the side of the valve cover. However, knowing when to stop tightening the valve cover bolts is pretty easy; as they sort of "bottom out". The banjo bolt is also pretty easy to figure out how tight is tight enough. The important thing here is not to over tighten either one of these/any bolts - as the last thing you want to do is snap a bolt.
The torque wrench I use for spark plugs and the banjo bolt is a cheap 3/8" one from Harbor Freight (~ $22). Again, it surprisingly reviews pretty accurate by numerous reviewers who have tested it - especially great for the price. The manufacturer claims accuracy +/- 4% and the range of the 3/8" size is 5-80 ft/lbs. This makes it usable for most wheels (~ 80 ft lbs) and most regular bolts. You can get a torque wrench that is more precise than 4% accuracy. Most torque wrenches are not quite as accurate at their lower measurements (~ 15-20% off at the lowest 20% of their scale) However, plan to spend 3-8x as much. I don't know if I would be using the Harbor Freight torque wrench to torque rod or main bearings - but I bought it mainly to ballpark most car wheel lugs. Of course, it would be ideal to have a torque wrench in 1/4", 3/8", and 1/2".... However, a 3/8" is a good compromise if you only want to buy one for general work. When working with a torque wrench always handle it gently and torque bolts slowly.
6. 1/2" drive 32mm Socket & 1/2" Drive Long Handle Ratchet:
Not too much to say here. You will need a 32mm socket to turn the crankshaft bolt. That in turn will turn the timing chain which will turn the cams - so you can adjust the valves while they are unloaded. You can get any generic 32mm socket at most Pep Boys type places.
Early S54 engines do not have a 32mm bolt at the crankshaft. They have four protruding external Torx head type bolts. You can not use a 32mm socket to turn the crankshaft with this set up. You should be able to use a 36mm 12 point 1/2" drive socket, or BMW has a special tool for this: BMW crankshaft turning socket (83-30-0-491-056). However, these where not fitted to any Z4 M cars - only early E46 M.
The job will be much easier with a long 1/2" handle ratchet. This is because the crankshaft is at the bottom of the engine, and on E85 M it's pretty hard to reach your hand down there. Also, a longer handle ratchet will give you more leverage turning the engine. A long handle ratchet helps a lot. The one I'm using is from Harbor Freight as well. It's 1/2" drive with a telescoping handle. It extends to 17" and costs about $17. It's more than enough to do this job. You will also need a 1/2" extension that is about 2.5" long.
7. BMW S54 Valve Adjustment Kit & Shim Installer Tool
The "shim kit" comes with shims you need to adjust valve lash on the S54 engine. The BMW part number is: shim set #11340031525. The kit comes with 6 shims of 23 sizes (138 shims) in a case with space for 6 extra shims. The BMW part number for the shim installer tool is: #83300493743. Each different size of shim has a BMW part number as well. The tool is a bent magnetized "stick" that allows you to easily pick up the valve shim from the top of the valve via magnetism once the rocker arm is unlocked and slid over. It is also used to install the new shim.
Some have fabricated their own tool using various things and a magnet. It's not worth the hassle for me - so I'd just recommend getting the pre-made tool. The tool is important - as the last thing you want to do is to loose a shim in the engine compartment or in the actual engine (gasp!) somewhere.
I've seen the shim kits online priced anywhere from $390-$600. So prices vary - shop around. Picking up a used shim kit may be a viable option - but you may want to find out if the kit is complete or what shims are missing first. Since replacement of a shim leaves you with an old shim to store in your kit - the kit may look "complete"; but may contain "old shims" of various sizes. Using "old shims" is no problem; as long as the are of the correct thickness and do not look dished or especially worn (unlikely - unless they came from an oil starved engine).
Shims can also be purchased individually from BMW in all the sizes the kit contains. However, this will likely require ordering shims from the dealer or online, unless you know of a dealer that stocks all the shim sizes. This also will likely require the car being down for several days while you are waiting for your shims. Another point is, while the shims are pre-measured in certain sizes and you should get a shim exactly the size that is stamped on it -this may not always be the case. Sometimes the shim you need may be on the borderline and the shim you order may be a hair off. So, this puts you back to square one ordering another shim if the clearance isn't correct.
To me, it's just not worth it. So, if you can afford it and plan on keeping your S54 vehicle - I'd just buy the whole set. Another point is, used shim kits sell on eBay for almost the price of a new kit. So, worse case scenario is you could sell it after using it for almost what you paid for it. If you want to keep the kit "complete" - you can order replacement shims from BMW to make up for the shims you use during your adjustment.
While the price of the shim kit is a bit costly, there are alternatives (generics). This is up to you if you "trust" these shims are just as good. I have read they are - but can't vouch for them myself. The popular alternative shim kit is from WiseCo (VSK4) and costs about $40.
8. Other Stuff
You will also need common hand tools: ratchets, extensions, screwdrivers, pliers, sockets, Torx sockets, parts brush, small picks, and a 5/8" spark plug socket with rubber holder inside (almost all these sockets have this). I also recommend picking up some type of small plastic scraper to remove the little bit of RTV that will stick on the head once the valve cover is removed. Pick up a few rolls of mechanics disposable towels as well. Small plastic baggies are good to place your nuts and bolts in to keep them separate, organized, and from getting lost.
You should also get a small tube of anti-seize for the spark plug threads and some di-electric grease for the spark plug boots. I'd also recommend a tube of engine assembly grease to aid in holding the shims in place on top of the valve while you reinstall the rocker arms. Having a paint pen, Sharpie, or wax crayon is also a good idea - in case there is anything you want to mark (connectors, coils, etc...). Lay everything out you will need before starting and work in a clean and organized environment.
9. Parts
You will need some parts to complete the job. The valve cover gasket is technically reusable, but I think it's a better idea just to replace it - along with the 15 grommets that go with its mounting. I also recommend picking up one of each of the two types of valve cover fastener assemblies (nuts/studs along with washers) in case one is inadvertently broken or dropped and lost in the engine compartment during disassembly. They are only a few dollars.
The brass crush washers for the oil feed banjo bolt are single use and need to be replaced. You will also need 6 new spark plugs. I recommend buying all BMW brand parts to save yourself any headache of dealing with aftermarket parts that are close - but not close enough.
BMW part numbers:
Valve cover gasket (1): 11 12 7 832 034
Rubber seal / grommet (13): 11 12 7 830 972
Rubber seal / grommet (2) 11 12 1 437 395
Cap nut assembly (extra stud/washer/grommet for valve cover in case lost): 11 12 7 838 078
Cap nut assembly (extra nut/washer/grommet for valve cover in case lost): 11 12 7 838 075
Profile (spark plug) gasket (6): 11 12 7 831 271
Gasket ring / copper washers: (at least 2): 07 11 9 963 129
BMW shim kit (1): 11 34 0 031 525
BMW shim installation tool (1): 83 30 0 493 743
Spark plugs [NGK DCPR8EKP] (6): 12 12 0 022 902
Most of what you'll need (minus basic hand tools, di-electric grease, torque wrench, and engine assembly grease):
BMW Shim Kit:
S54 Z4 M Roadster:
****Procedure:
First, it's always recommended to disconnect the battery when working on or disconnecting anything electrical. Make sure you either remove the keys from the vehicle or leave the window open before disconnecting the battery. In the Z4 M the battery is in the trunk. First thing to do is raise the rear deck lid shelf by turning both nobs up. This will give you access to the mobility kit and then the battery cover top bolts:
Then remove the mobility kit and air pump from the top of the battery cover. These are held on by Velcro straps and easily removed by undoing the Velcro.
Pieces removed and set aside in trunk:
Now, remove the three 10mm bolts holding the top part of the battery tray to the car. Two have been removed in the picture:
Next, remove the 3 plastic screw rivets holding the battery cover on. These have a phillips head and 10 mm socket head built into one. These can be tough to remove completely without breaking. The best way I have found to do this is to use a 10mm 1/4" drive socket to loosen the plastic screw until it doesn't want to turn any more or starts to push in from pressure from the socket. Then, unscrew it the rest of the way by putting a towel over your fingers and using your hands - while gently pulling out on the rivet head.
3 plastic rivets location:
Rivet:
Set bolts and rivets aside in trunk pocket:
Now you can remove battery cover by slightly lifting up and pulling out on it.
Removed:
Now, disconnect and set aside the negative battery cable (brown) using a 10 mm socket or wrench:
It will be necessary to remove the plastic BMW radiator cover trim and the electric cooling fan on Z4 M to gain access to the crankshaft pulley bolt (necessary to rotate engine). The trim piece is held on by 8 plastic rivets (red in photo - phillips head) and 2 metal Torx bolts (green in photo - T 30 Torx). Remove these as noted in photo:
These plastic rivets are exposed to engine heat and dirt and can be extra difficult to remove without breaking. They are phillips head only and similar to the rivets holding the battery tray in the trunk. I have found the best way to remove these is to turn them as far as they will go with a screwdriver (phillips), then place a towel over your hand and try to remove - like the trunk rivets. As a last resort, if one is extra difficult, gently grip the head and turn with pliers while pulling up:
If your pulling up with pliers or your fingers covered with a towel while unscrewing a rivet, it will come out in one piece (plastic rivet head and base).
Remove the T30 metal Torx bolts (2):
After this the plastic cover will come up giving you access to the electric fan. Plastic cover and fasteners removed:
You now have access to remove the electric cooling fan:
First, disconnect the 2 electrical connectors on the top of the fan (left and right side):
Side aside the connecting wires. The cooling fan is held on the car by one plastic push rivet (driver's side) and one metal screw (Torx T27 - passenger's side) only. Remove the plastic rivet head (slide fit - no threads) by gently prying it away with one or two flat head screwdrivers. Then, once there is a gap between the rivet head and the base, pull the head/stem out with needle nose pliers utilizing the gap space:
The plastic rivet head/stem will likely come out by itself. After its removal, gently pry out the base with a small flat head screwdriver or pick. Be careful not to drop it:
Now, remove the Torx T 27 screw from attaching the cooling fan to the car. This screw can be delicate and tight to remove. Be careful no to strip the Torx head:
If the Torx head gets harder/tighter to remover once initially broken free, remove the rest of the way by gently by gripping screw head with pliers and rotating loose, as not to strip the Torx head. Now, the electric fan is free to be removed from the vehicle. Carefully lift it up and out. Both the radiator hoses and a thin plastic coolant pipe will be slightly in your way. Be extremely carefully of the plastic coolant pipe, as noted in photo:
Plastic rivet and T 27 Torx fasteners that hold fan to vehicle:
Cooling fan coming out:
Now you will have space to access to he crankshaft 32mm bolt required to turn the engine:
This is the view of the 32mm socket, small extension, and long 1/2" drive ratchet on crankshaft bolt:
After this, remove the plastic breather vent tube from valve cover and intake plenum. This is done by first removing the electrical connector on the solenoid by pushing down on the metal connector retainer while pulling the connector out. Do not remove the metal retainer clip from the connector - pushing down on it will release the connector.
Then, remove the vent tube. Squeeze the end connectors on the tube as directed in the photo below. Gently pull and wiggle the ends of the tube and pull up. This plastic is delicate and can easily break - be careful:
All disconnected:
Early M3s do not have the electrical solenoid on the breather vent hose - so on these you simply can remove the hose and set it aside. I believe all Z4 M has the solenoid, and it's hose is connected to a pipe via rubber tubing with factory clamps. I recommend not messing with these clamps and simply holding it out of the way during the work with a screwdriver (it will stay put):
Despite appearance, the black textured plastic piece you see with the "M" logo in the front is not the valve cover. It's a plastic engine cover hiding a bunch of wiring for the coils, oxygen sensors, etc... This cover is held on by six 10 mm metal nuts. Remove these nuts:
After removing the nuts, remove the plastic cover. It's necessary to remove the oil cap to remove the plastic cover. When the cover is removed, reinstall the oil cap on the aluminum valve cover, to prevent anything from falling in the engine. Reinstall the oil cap on the valve cover until it's time to reinstall the plastic engine cover during reassembly.
Note, on Z4 M, at no point from this point on is necessary to disconnect any electrical connectors other than the connectors to the actual ignition coils themselves. The wires harness' can be moved out of the way for access without disconnecting anything else.
Push in the 2 sets of retaining clips holding the harness, then gently rock the harness loose - but do not completely remove it out of the way:
Now, remove two 8 mm harness connector retaining bolts at the top end intake side of valve cover. Also, gently and careful free the wires (as circled in photo) from their metal guides in valve cover:
Remove harness wires in back of valve cover from all similar guides:
After that, remove rubber grommets that allow harness to pass through engine cover and valve cover:
Now, it is possible to lift wire harness away and set it aside as shown:
All you are left with now is the coil pack harness. It is held on with the same 8 mm bolts holding the other harness' connectors. Remove the bolts:
Once the bolts are removed, unlock each coil pack connector by lifting up on the retainer to unlock the connector:
All coil packs unlocked and all 8 mm harness retainer bolts removed:
The last thing required to remove this harness is to remove the ground strap (lower in photo) which bolts to the side of the engine block (13 mm):
At this point you are able to remove the coil pack harness completely from the valve cover. Place it towards the back of the engine out of the way as shown:
Remove the 6 ignition coils by placing a long extension or bar through the holes on their tops - while gently pulling up and wiggling slightly. Some force is required to remove the coils, they are press fit into the head:
While there is no real reason to do so, I recommend numbering each coil (1-6) so they can be placed back in their original cylinder:
The last thing to do before removing the valve cover is to remove the oil return line. This is a hollow 17 mm banjo bolt with two copper gaskets between it and the the valve cover:
