Did you hear any lower end knocking? A really bad rod bearing could lower the compression result. How much I am not sure and it would have to be a pretty bad bearing to do so.

Might hold together with the cylinder not firing. Cylinder firing the rod is gone in a situation as bad as that. Usually the number one rod lets go on the four cylinder 616 before compression is lost.

Why such a crazy thought? Adding oil to the cylinder gave no upside at all. You had a hundred pound compression with or without it.

No. There wasn't any lower end knocking.

Just to be sure I am clear. To my knowledge we have never had a case on this site with a 616. Any additional rod bearing clearance drops compression though.

It would take those rod bearings being in an overlap situation. This would jam up an engine . To drop off compression to a hundred pounds. Or horribly worn down well into the bearing material backing.

Actually we do have regular cases of diminished compression with the 3.5 litre diesel blocks. The rods bend a little and the compression becomes so low that cylinder will not fire. Generally speaking rods on the 616 are not plagued with this issue. A much more rugged engine from a time quality was dealt with properly.

I suspect you will probably find a piston/ wall issue really. Or perhaps broken rings. I also hear the pain of sending out the head.

For future reference. I set the head upside down and introduce a little thin fluid to see how the valves are seating. Before taking a head to a machine shop and after it comes back.

Since I have limited ability I also introduce air pressure to any suspect cylinder to find out where it is going. Unfortunatly I have little time to work on mechanical systems now. I can only hope some time gets freed up as I enjoy it when I do.

The 616 is no rocket ship but I truly like the two I have. If only a couple or even just one five speed manual transmission could be obtained for them would make my day.

In case anyone missed it... the easy way to get a W201 5-speed to mate to your OM61X

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"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."