AMG3.2's DIY Headbolt Adventure












First a glamour shot at the end of the day:

Now some more pics:
Uhh - do these cams look brand new?

Marking everything up because I'm paranoid and still a bit uneasy about timing.


Also, when I removed the cam phasers, I didn't see this "diamond" washer anywhere... I'll have to look again but I haven't seen anything that resembles it unless it's really stuck on the phasers.
Edit: They were in there stuck to the inside of the phasers. Just remove and replace. They're just a very very thin washer.
Tappets look to be in decent shape, right?

FYI's for future DIY'ers:
The bolt to hold the cam phaser in place is a M5/8 bolt. I bought an M5/10 and it fit perfectly. FYI.
Taking the pulley just about the main crank is super beneficial to see the 40 degree marking. Super easy at that point.
Precision is key when torquing down these fasteners. Buy good torque wrenches. In my case I bought a 2 CDI's (one for low torque and one for medium to high (100 ft lbs.)
Another part needed to move cams into TDC 40 degree position after reinstalling: Locking pliers and a 28mm wrench. The longer the wrench the better as moving the cams under spring load takes a bit of muscle. Once you have the cams installed and back in their rough orientation (mark them at the beginning with nail polish like I did so you know which way is right side up) use the flatblade portion of the M156 timing tools.
I didn't understand how it worked until I saw the cams and got into it but it's super easy. The back of the cams have a horizontal notch in them. Use the 28mm wrench to move the cams around in a clockwise and anti-clockwise fashion until the flatblade slides in place at the back of the cams. Once the straight edge is in place, they hold the cams in place as the straightedge rests against the casing of the head. At this point, cams are timed. Then move on to installing the camshaft phaser.

For the phaser install, simply install them onto the cams in their rough orientation. Trust me, it doesn't matter how they go back on. However, only remove the M5-8 screw or holding device AFTER the phaser has been installed onto the cam.

After this is done, install the camshaft holding device at the front on the engine where you used your 28MM wrench. Now tighten to spec which can be found in the PDF's in this thread. With the bolt still finger tight, rotate the front piece until the plate fits on it. Those little spikes fit perfectly into the openings of the front piece and thus time it back to 40 degrees TDC.
]Tighten the phaser bolts (new hardware) and make sure to install a new diamond washer where the phaser meets the cam (if memory serves me correctly)
Last edited by AMG3.2; Jul 20, 2017 at 11:24 AM.
The Best of Mercedes & AMG
You didn't need to fully remove the cam phaser from the cam just loosen the bolt is fine, no big deal but just makes it easier.
Yes the heads can come off with the engine in the bay. Unless you have arp head studs then you can't.
Don't worry about markings on the cams. With the tools and when you see how they work and understand, it's impossible to physically put them in wrong with the 3 tools installed and the engine at 40 degrees.
Taking that pulley off is way easier to see the 40 mark, good tip.




You didn't need to fully remove the cam phaser from the cam just loosen the bolt is fine, no big deal but just makes it easier.
Yes the heads can come off with the engine in the bay. Unless you have arp head studs then you can't.
Don't worry about markings on the cams. With the tools and when you see how they work and understand, it's impossible to physically put them in wrong with the 3 tools installed and the engine at 40 degrees.
Taking that pulley off is way easier to see the 40 mark, good tip.
Took one head bolt out and realized I didn't drain the coolant. I kept pumping the coolant from the bolt hole and was like damn this is a lot. I made sure to vaccuum all of the coolant from the bolt holes though.
Bolt looked pretty good actually. Will post pics possible later today if I keep working on it.
I can have a bolt removed from the engine for an hour or two without worries or some type of gasket failure or something right?
Also, when do I do the oil change? Right after I'm all done and before starting the car, or let it run for a few mins then do it??
EDIT: Merc and Jasonoff, just to play it safe, I'll just go ahead with replacing the tappets.
Last edited by AMG3.2; Jul 20, 2017 at 11:32 AM.
https://en.wikipedia.org/wiki/Hydraulic_tappet
Hydraulic bucket tappet design in the M156 which is a "hydraulic valve lifter".
How many miles are on your car and can you post a picture of this bolt?




Another thing I would do, once the initial outcome is good and you start up fine, is to buy that chemical head gasket tester kit from pep boys and confirm that they are still in good shape.





I would say the oil change before or after wouldn't matter. Your HG wasn't compromised.




Well. Looks like I messed up somewhere along the way. FML to the utmost extreme.
Three things happening that are leading me to this conclusion.
1) Loud tapping noise that wasn't there before. Almost like now my tappets have gone bad.
2) Smoke coming from both sides of the engine. Could be burning residual oil spoiled while removing bolts etc, but thinking it's just a compromised head gasket.
3) When I shut the engine off, a hissing noise occurs immidately. Again, thinking somewhere in the cooling system, there's a void.
Video:
http://vid77.photobucket.com/albums/...pshe5pojvw.mp4
More coming soon
So lifter noise has subsided alot. Much better now and I think the smoke is burning oil off the headers. It doesn't smell like coolant so I'm feeling a bit better.
Still don't know about the hissing noise after I turn the car off though.
Last edited by AMG3.2; Sep 25, 2016 at 04:56 PM.








