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Discussion Starter #1 (Edited)
Dear Members,

I just finished rebuilding my M119 engine on a 1995 S420. After I completed all the work and re-assembled the entire engine, there is binding when the crankshaft is rotated in a clockwise manner. The engine and transmission are in the car. Compression is about 195 and constant at all cylinders. Shouldn't it be over 200?:confused:

Sounds like a timing issue. Valve is hitting piston. But, what is most confusing is that I have made sure that all four camshafts are positioned properly for timing. I have used the pins to ensure proper alignment. Also, the timing adjustment for the camshaft gears were performed when the number one piston is on the compression stroke. Unless I am technically incorrect, what the heck is happening??:crybaby2:

Is there any way that the crankshaft assembly was put back together incorrectly? Or, is the crankshaft dampner and pully mis-aligned relative to the crankshaft?

Any thoughts!!!
 

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Did you disassemble with engine in TDC or OTDC ??
(TopDeadCenter or OppositTopDeadCenter ...)
I havn't done a chain/cam-job on a V8 before, but have done many R4 and R6's..
It can be quite easy to do it wrong.. Especially the TDC thing..

You have put something back together in the wrong order.. Or else the engine would turn just as before.
One must check every line-up mark, before disassembling, and then make sure nothing moves during the job..
Re-check your work..
Hope it's just a little mistake, and nothing $$$
 

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In addition to what Erik wrote, a few things come to mind (please don't take offense if these thoughts seem simple, I usually find that these problems are simple to fix, but the answer is easily overlooked);

-Clockwise? You mean from the front of the car I hope, just to be sure.
-Crank should be set to 45BTDC, with the cams pinned, then install the chain and tensioner. If it is set this way, I don't see how you could have an interference problem.
-Once I set up mine in this manner, I was able to crank the engine by hand using the bolt on the end of the crank. Three complete revolutions and all the holes in the cams should line up perfectly when the crank is at 45BTDC.
-If I remember correctly, the dampener can only be installed one way because one of the bolts securing it to the crank is offset slightly (I remember this from my R129 head gasket replacement)
 

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Dear Members,

I just finished rebuilding my M119 engine on a 1995 S420. After I completed all the work and re-assembled the entire engine, there is binding when the crankshaft is rotated in a clockwise manner. The engine and transmission are in the car. Compression is about 195 and constant at all cylinders. Shouldn't it be over 200?:confused:
How did you determine the compression if you can not turn the engine?
 

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How did you determine the compression if you can not turn the engine?
ditto, not to mention these enginges run on the very low end, 130-145psi is considered good for these babies...
 

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I just timed a m119, The post named"500sel head gaskets". I walk you throught the timing procedure step by step with pictures. Take a look at that thread. By the way it sounds i agree with everyone elses comments, sounds like cam to crank timing is off. timing on the m119 is set at 45deg btdc. Check it out may help you. Have fun!
 
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