Hello again Friends,

I just did a compression test on my 1984 500 SEL. On the right bank every cylinder showed values of 180-185 PSI but on the left bank they were all 140-145 PSI.

When I added oil the values went up with 20 PSI which looks kind of normal to me.

What I think is a bit strange is that the higher values are on one side and the lower on the other.

Does anyone have any thoughts of this is normal.

I kind of suspects that maybe the valvetiming is NOK on the left side. I did change the cam chain and the tensioner and guides a couple of months ago and the timing marks did not line up as the should (when the cam timing marks lined up, the crank showed 14 BTDC degrees). Before I changed the tensioner etc the crank showed 28 BTDC degrees. I tried to offset the timing with one tooth and then the timing at the crank showed about 5 ATDC degrees but the engine hardly ran and was making a lot of valvetrain noise so I set everything back as it was timed before the parts exchabge.

Please advise.

Mikael Westerberg
1984 500 SEL
Vanersborg, Sweden