Compression test results

[sleam]

I have a 1972 SIII with a 2.25 petrol engine.
After seeing the blue smoke getting worse I did test the engine today. Smoke is less when the engine is warm but does blow out some when changing gears going up hill. Here are the compression test results for you all! #1 dry = 80psi and wet = 90. #2 dry= 75, wet = 90. #3 dry= 75, wet = 90. #4 dry= 90 and wet =90.
Thoughts? Valves? Head gasket? Something else? What do you recommend I do/ get done?
Thanks, S

[stomper]

Rings.

[ignotus]

If your timing is correct, I agree, valves. compression should be 145. IIRC

Oops! Meant to say rings not valves(had them on my mind though...)

[stomper]

If the issue were just valves, there should not have been any appreciable difference in your wet and dry compression tests, as the main purpose for doing a wet test is to temporarily seal up the rings to boost the compression numbers. Also, valves shouldn't be leaking oil into the exhaust to create blue smoke. Blue smoke occurs when the oil slips past the compression rings into the burn chamber of the cylinder, and is ignighted as part of the combustion stroke. The smoke then is pushed out through the exhaust valve and through the tailpipe during the normal function of the engine.

It is entirely possible that your valves are not seated properly, and that is causing a reduction in your compression as well. How much oil are you loosing? how bad is the smoke out the tailpipe? how many miles are on the engine, and have you ever had a rebuild of it in the past? I personally would consider pulling the head, having it rebuilt locally, and inspect the pistons and rings and cylinder bores while you are in there. If the valves are burnt, pitted or bent, you will improve the compression significantly by just rebuilding the head. You may be able to get away with putting off doing the rings and pistons for quite a while, or once you have looked around in there, you may decide it would be best to have the whole engine rebuilt.

I am NOT a super skilled mechanic, and others may chime in here and disagree with my recommendations. That's fine by me, I am giving you my honest opinion about how I personally would proceed. I'd love some others to weigh in, so if I am wrong, I can learn what to do if this ever happens to me.

[sleam]

I realised that this engine probably has not been converted to unleaded and that would be part of the problem. I'll get some lead additive and Restore for now but I think the rebuild is the next project. Well, next job to go to somewhere and get it done! That's beyond me and my ability and tools.
I'm not losing much oil at all, some but negligible. I'm at 7000 ft so that would make a difference too I hear. It's got 114,500 miles.
Thanks for your ideas.

[I Leak Oil]

Sounds like rings. The blue smoke could be a compilation of valve stem seals, rings and just general high wear.

[Zimbos]

WHAT WEIGHT OIL ARE YOU USING , I RECENTLY HAD A MOTOR THAT WAS LOCKED UP AND AFTER GETTING IT FREED NUMBER 2 CYLINDER WAS WET I PUT 20-50 OIL IN THE MOTOR WITH A QUART OF MARVEL MYSTERY OIL IN , THE LAST TWO TIMES I HAVE CHECKED NUMBER 2 IS DRY , GOOD LUCK STAY THIRSTY MY FRIENDS

[I Leak Oil]

Thanks, now I AM thirsty!!!!
10W40 run all year round here.

[sleam]

I hadn't thought about the oil. it's 10-30 for winter but yeah, a heavier one makes sense. I added "Restore" to the engine yesterday too. And a lead additive to a full fuel tank.