Just wanted to leave some feedback for RacerX5 on this tool rental, and leave some comments on performing the job.
RacerX5 kept in good contact throughout the entire transaction, even a phone call to give me some pointers and to remember to keep a level head when the job gets tough. He shipped the tooling promptly, and when received the kit back, promptly refunded my deposit. A++, no hesitations to deal with him again.
As for the job itself; READ ALL OF THIS BEFORE YOU START.
2006 X5 4.8is, 121k miles, with mostly regular maintenance intervals, I have most records from new, and this was a CPO vehicle with the second owner, it was well cared for. I performed job engine in.
Symptoms were as everyone says, after long idle, hot day in traffic, plumes of WHITE smoke, and sometimes some water droplets building up at the tips. I was burning oil, and losing no coolant, so no confusion on this being crankcase/valve stem seal issue.
I have been working on cars professionally for 15+ years, albeit not for BMW, they have just been a passion, SO first time digging into the N62, but I have work experience in this department. That being said... your patience will be greatly tested. Do everything slowly.
Some helpful tips,
-Remove the ALL of the cowling and "storage boxes" for the DME and brake master cylinder around the engine before getting started. Some of these "plastics" will be brittle, I replaced a few of them.
-Double check that you removed all the bolts for the valve covers before trying to remove them, and even when you have removed all of them, they will still feel bolted on, rock back and forth, etc.
-With all spark plugs removed, I did one bank at a time, rotating to next TDC in order, use a thin long armed ratcheting breaker bar, try to avoid breaking coolant lines when cranking engine, go slow.
-Have a vacuum handy and a thin hose to tape to the end of the vacuum hose, I had one small enough to reach into the oil drain ports, you will have some hard rubber around from aged seals cracking.
-BEFORE removing any valve keepers on any valve stem, while using the leak down tester to pressurize the cylinder (I used 50PSI), and the valve spring is compressed, you can test to be sure the vale will stay up by pushing down on the stem to be sure it will not drop into the cylinder.
-Always have all spark plug holes covered, either with supplied plugs in kit, or your existing spark plugs.
-Always have the oil drain holes plugged with plugs supplied in kit, on the bank you are working on.
-Always cover the area where the timing cover hole of death exists.. whatever you drop in here, straight to the oil pan, or worse, stuck in a gear/chain.
Steps per valve stem seal for me (your approach may differ!)
1. Using TDC flag, find TDC. Ensure cam lobes are not compressing any springs (this means a valve is open, ala no pressure using leak down tester).
2. Install TDC chain lock tool, you dont need to tighten this tool too much, just a light grip will do.
3. Remove TDC flag and spark plug.. plug, and install the leak-down tester, test to ensure you have little leakage, it is normal to have a small amount of leakage. If you have a lot of leakage, remove chain
lock tool, and try finding TDC again, if you cannot get good leakage results, you may have a bad valve seat or valve guide/piston rings, further diagnosis may be needed. REMOVE Air pressure before
continuing.
4. Compress the spring with retainer (you may need to push the valve stem and keepers down with the spring using your finger), remove the rocker arm. For the INTAKE rocker arms, I removed them and
set them aside when working on that valve stem. For the EXHAUST rocker arms, you can just push them to the side, you dont need to remove them completely from the lifter (also hard to get a finger
in there to remove and reinstall.)
5. Compress the spring of the valve you are working on (the four springs surrounding the spark plug hole, or the leak down tester hose), BEFORE removing the keepers, TEST push the valve stem to make
sure you have good cylinder pressure.
6. Remove the keepers (I used a magnet here).
7. Try to keep the retainer centered around the stem, decompress the valve spring, remove the retainer and spring (again, a magnet). For the INTAKE valve stem at the front-most to the front of the
vehicle, I had to remove the VVT arm, but nothing more. Pay attention here, the spring sits inside "v" shaped little tabs, I've read they are easy to break the little tabs off, so be careful reinstalling the
spring to its home when you reinstall the arm, I used a small flat pry-bar here at an intelligently placed location to pry the spring into place, but be careful. I think the install was in an upward motion.
8. Thinking of the stem as your axis, using the valve stem seal removing pliers, stem as your axis, attempt a twisting motion to break the seal loose, remember these have been in here a while, pulling
straight up is not the answer, you can see them break loose while you are twisting, then pull up.
9. Install the stainless steel valve stem seal protector over the stem, you can use a magnet here to install it in the tighter areas, my fingers didnt fit near the intake stems.
10. Install the new valve stem seal, again a twisting motion to seat the seal properly. Do your best to completely close the gap between the new seal metal ring and the cylinder head, but also keep in
mind this will be held down and pressure given from the valve spring at whatever RPM the engine is spinning.
11. Remove the valve stem seal protector (Use a magnet).
12. Reinstall the spring and spring retainer.
13. IMPORTANT: Keep the spring retainer centered around the stem when compressing the spring, as you CAN catch the grooves where the keeper goes and press the valve down, lose cylinder pressure,
and drop the valve into the combustion chamber (this didnt happen to me, but you dont want to do this, I have read horror stories.) At TDC this doesnt go far, but i dont believe the stem is showing at
this point.
14.When you have enough room to install the keeper do so either using the provided tool (I didnt, I couldnt get a great angle using the provided tool) or use a screwdriver with some HD grease and
patience. Use two screwdrivers, chopsticks, one magnetic one not, I used a combination of all these things, whatever works for you to ensure the keeper gets installed to the valve properly.
15. When decompressing the spring, ensure the keepers and things look assembled properly, the keepers will sit below the top of the spring retainer. Be confident on your assembly here.
16. Remove the air pressure from the leak down tester.
17. Compress the spring AGAIN, ensure to push down the valve stem and keepers together while compressing, (I had to use my finger to push the stem down while compressing the spring).
18. Re-install the rocker arm onto the lifter "nub", and while decompressing the spring, ensure the other side of the arm is properly centered on top of the valve stem.
19. Do this 31 more times!
Some additional things to keep in mind..
-For the two rear most INTAKE spring areas on each bank, you will probably need to use a mirror for all of the steps and think backwards, this is probably where you will start thinking you should've hired
someone to do this.
-ALWAYS keep an eye on your leak tester pressure when your keepers and retainers are out, if this drops for whatever reason, power outage, hole in supply hose, compressor is off.. whatever.. the valve
can drop if not being retained.
-If after doing one or more of the 4 valve stem seals on the SAME cylinder you cannot achieve proper leak down (proper cylinder pressure), then you may try rotating the engine to re-seat the valves, as
the tool does not allow the valve to "snap" back against the seat, thus not providing a total seal. You can also remove the rocker arm again from the offending valve (PITA, i know). I found this issue to
usually be on the intake valves.
You may still have a small amount of white smoke, keep in mind things are seating and there was probably some remaining oil to burn off, if this continues recheck your CCV connections (I had a loose one to the valve cover!)
Installing the valve covers is as much of a pain as it was to get them off! lube the spark plug tubes, and look at the inside, bottom of the valve cover to find the brown plastic things that ride just along the inside of the head to see where to focus on proper installation.
I also replaced the front timing cover gaskets, the front VVT solenoid inner and outer o-rings, all cam sensor o-rings, and resealed the cam-driven vacuum pump.
For the front timing cover gaskets, if you decide to do them (you should), you do not need to completely remove the alternator or bracket, just the top bolt, loosen the bottom bolt to swing the alternator outward and BUY a long reach thin e-torx socket to reach the "hidden" bottom timing cover bolt.
It definitely takes AT LEAST 20 hours, check, recheck, and check everything five more times to make sure you arent about to screw something up, and dont leave the oil hole plugs in when you put the valve cover back on.
All of that said, my 4.8is smokes NONE after this repair, and with things like new spark plugs and air filter, it runs better than I have ever experienced it run, and it will happily run another 100k. Its worth every bit of frustration I endured.
-Devin
Last edited by e30devo; 02-01-2018 at 12:14 AM.
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Originally Posted by Noodleman2u
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