I'm with Peter on this one. First chain replacement I ever did was on almost the same engine (OM617.912) and I also managed to skip a tooth, but checked my work, found the problem, and corrected it. If you don't want to pull the pre-chamber (I didn't either), I think you'll have to determine "skip" or "not skip" by experimentation. Rotate the engine through several complete revolutions by hand to make sure there's no piston/valve interference, button up and drive the car and judge the power output. If not satisfactory, move chain one tooth on camshaft gear, verify no interference between pistons/valves, then check the power output for improvement. Decide which position is better.
I'll bet that your harmonic balancer is fine and is reading true. -Max -----Original Message----- From: mercedes-boun...@okiebenz.com [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Peter Frederick Sent: Friday, November 05, 2010 8:24 PM To: Mercedes Discussion List Subject: Re: [MBZ] OM617 - Identifying real crank position Yes, you can remove the bottom oil pan. Messy, but should work. You can also pull the #1 prechamber and use something like a coat hanger wire to determine when the piston is at TDC. Even just pulling the injector or glow plug should let you know if you are close. Stops blowing and starts sucking in air at TDC on the compression stroke. Or you can assume you have jumped a tooth, which is rather common -- I've done it twice. I believe they are 13 degrees each, so it ads up pretty well, and you would be within 2 degrees if you move the cam sprocket. It will run just fine, although low on power with the cam 15 degrees late. 15 advance and the pistons hit the valves. Peter _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
