I've got 71 2.8 mercedes 6 cyl with low compression (130) in just one cyl,
compared to 140-150 in the others. Unfortunately cyl on either side of the low are 140 and 150, worried about that imbalance . Overheated at some point- machined the head, new gasket ,no valve work just re-set. Walls of
cyl #5 are not nearly as clean as the rest

You are close to the 15% allowable difference in compression between cylinders. One cylinder is slightly less efficient as you read it then the others. But it is still putting out a lot of power. If you just did the head work described, I would begin to drive it and get some miles on it. Then ninety days down the road check the compression again. You might be surprised at the reading you get.

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Junqueyardjim
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1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
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Did you rering it ? If not try using some engine flush and retest after an oil change.

Retorque the head and then do a comp test. Then do a leakdown test.

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A Dalton

great thanks for all the help!