Hello,

Each timing chain link is equal to eighteen degrees. It is not unusual for the timing slot on the washer to be a bit late getting to the mark on the camstand. Chains become longer with wear. A slight cut on a cylinder head becomes twice as much slack on a chain.

Most of the time normal chain wear from miles or repairs does not make much difference. Unless it is just set wrong, I find it difficult to believe that this can be the problem.

These early engines had lower compression than the later M130 engines etc. Look on the cylinder head near the casting number on the spark plug side and you will see the actual compression ratio cast into the head. It should read 8.7 to 1 That's not much psi if you do the math. I am figuring around 140 to 150 lbs max, even with carbon build up.

Often times when a head is cut, they also cut the top to flatten everything out again to allow the cam to turn freely. The book suggests shims under the camstands if needed. My old MB shop manuals also state than off set keys usually "make no noticable difference" at least on these earlier engines.

Anyway you are probably going about it correctly. Check all the cheap fixes first. A new cylinder head would be pricey.

__________________
Joe Alexander
Blacklick, Ohio
1964 220SE Rally (La Carrera Panamericana someday)
1966 Unimog 404s (Swedish Army)
1969 300SEL 6.3 (sold)
1969 280SL Pagoda
1973 280SEL 4.5
1974 450SLC FIA Rally car (standard trans)
1982 300D turbo (winter driver)
1986 560SEC
1989 Unimog FLU419 (US Army)
1991 300TE (wife)
2002 SLK 32 AMG (350 hp)