M104 timing
 

Posted this on benzworld and got no response. They seem to be more interested in heated seat problems and discussing whether it's sacrilege to add a cup holder to 124's

Just did the head gasket on the E320 with M104.99. It's my first time doing a job this involved but everything is going well so far. Engine now seems to run OK with no oil leaks or coolant trouble but has a bit of what sounds like lifter noise.

With my 4 mm pins in and level, I am about 5 or 6 degrees past TDC according to the marks on the HB. Is this close enough or does it sound like it's 1 tooth off?

Should I pull the tensioner, top timing cover, lift the chain with the 4mm pins in position, turn the engine by hand to exactly TDC and re-lay it on the sprockets?

Just wondering here if 6 deg. at the crank sounds right for 1 tooth off and whether the variable valve timing is already capable of correcting for this amount of error. The cam adjuster was set to full retard before putting the chain on and re-installing the tensioner. Tension seems good

The marks I made on the chain and sprockets before disassembly are still lined up as are pre-exising marks that I see made by a previous person who must have been working on this engine. Could it have always been out a tooth and I didn't know it? It did run OK before the gasket failure, so I am wondering if I'm in about the right place already?

Most likely the chain is stretched, 1 tooth off is more than 6 degrees

15 degrees = 1 tooth if I remember correct.

Thanks for the replies. Much appreciated.

Should I be concerned about the chain if it is indeed stretch to this degree? (no pun intended) Or would this be a typical and unconcerning amount.

Mileage is only about 170,000 KM and I would imagine the chain is the original.

You will gain torque, a 4 degrees difference you will definetly feel, i rec a new chain , my 94 104 motor wagon has 197k miles and you can feel low end is not as good as it should be, ill soon be doing the chain and new motor,though i havent measured stretch,

Since I need the car to run, I have decided to button it all up and make a note for a chain replacement in the future - probably when I decide to replace the deteriorating wiring harness.

After tightening up the 3 exaust cam bolts (which were loose - a dangerous oversight that is now thankfully corrected) and doing a final cheap oil flush & filter change to rid myself of the remaining chocolate mouse in the engine from the head gasket failure, I have filled up with Mobil 1 synthetic 10-30 and everything now sounds quiet and smooth.

Just need to fix a cracked headlamp housing and attach the freshly painted bumper and I'm back on the road.

Thanks again to everyone who replied.

For what it's worth when I built my M104 I used a new chain and the bottom end was set to tdc using a dial gauge on cyl 1, not by the cool little timing mark on the front. Needless to say I was maybe 1-2 degrees advanced using a new chain according to my tdc readings, but it read about 4 degrees advanced on the damper. That damper is not accurate enough to be accurate to a degree or two, and 4 degrees should be fine.