[mark21]

hi there i am quite new (united kingdom) i own 1971 mercedes r107 sl 3.5l with m116 engine, 4 or 5 years ago i starting restoring most of the car and had the engine bottom end rebuild (piston rings all new bearing etc the but never got around to starting it so 4 years on engine in car turns over by hand fine the problem there seems to be about 5-10 degree play in the engine is this usual in this type of engine (cranks moves but the camshafts do not move till the crank mark ATDC get goes past 5 degrees and then (oil filler cap side) left camshaft timing marks line up but the right one is about 1-2mm short of the timing camshaft marks ? when the crankshaft is pointing to 7 degree ATDC the other timing mark line up perfect) before you ask i have replace timing chain and the metal chain guards (early type) when i rebuild the engine i have since (few days ago) replace both the camshaft sprockets and timing chain tensioner and try to line up the best i could but the timing mark are the same ,i can't find any play in chain by hand any advice would be very helpful thanks mark

 

[roncallo]

Yes this is normal because the timing chain tightener has bled down.

 

[MBGraham]

Yes this is normal because the timing chain tightener has bled down.

I recall once asking about this because we often check the timing chain with the engine cold.

What you suggested, and it seems good advice, is to use two wrenches. One to hold right side (passenger, USA, drivers UK) on it's mark. Then use second on crankshaft (or power steering) to tension the chain. This would take the tensioner out of the picture. Then check balancer and left side marks. If everything is new, they should line up. Maybe a bit off on an older engine.