3.2 liter M30 engine

Hi. I have a 732i 1986 that has some motor problems. Diagnosis so far: Engine runs very rough
Changed all spark plugs, no change.
Checked compression on cold engine
Cylinder, Comp 1, 11.5 kg (approx. 165 psi) 2, 0 kg 3, 0 kg 4, 8.5 kg (approx. 125 psi) 5, 8 kg (approx. 120 psi) 6, 10,75(approx. 155 psi)
I'm thinking the head gasket is blown as there is no compression on 2 cylinders next to each other. When I look at specifications for BMW engines it seems compression should be about 149 psi, so 2 of the cylinders are a bit hi and the working two others are a bit low, could this be due to broken piston rings? Allso I have no spec as to how much to tighten this spesific engine, the book I have lists all other engine types, but I'm hoping I can use the spec for 733i. Any thoughts on this, anyone?
Best regards
Lars
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into the head, then the rings are the likely reason. Otherwise, the head gasket is suspect.
It is no wonder that the engine runs rough. After all two cylinders are not working at all. Jim
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Depends. Cranking compression testing doesn't tell the full story, depending on what the problem is. Hence the big variation allowed while still within spec. At higher revs those cylinders may well do some work.
--
*OK, who stopped payment on my reality check?

Dave Plowman snipped-for-privacy@davenoise.co.uk London SW
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Allso I have no spec as to how much to tighten this spesific

trying again this weekend, I'll keep you updated on the progress
Regards
Lars
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