Inliners International Forums General Discussion Engines compression rings = oil rings?

Compression dry 1)145, 2)140, 3)145, 4)155, 5)150, 6)145
Compression wet 1)150, 2)155, 3)150, 4)165, 5)160, 6)160

compression rings seem ok, but what does this tell a person about the oil rings?

how do you detect a broken ring?

Thanks for your help.

Oil rings don't typically break. There more flexible than the cast compression rings are, plus their not subjected to the compressive forces generated by the cylinders. The figures you posted seem reasonable, so unless you are plagued with excessive oil comsumption or smoking, I don't think you have anything to be concerned with.

Hi true blue . . .

An oil ring prevents oil from getting 'up top' in the first place . . . and getting used/burnt in the business of combustion . . . this why some refer to them as 'oil control' rings . . .

Wet testing puts oil in the top straight away . . . this over abundance of oil creates a temporarily stronger seal between ring and bore. Large variances between wet and dry pressures is typically indication of out-of-round; taper or both in the cylinder bore. Oil can also modestly improve the pressures in a cylinder with slowly leaking valve or hair-line cracked head-gasket (both of which a leak down test will confirm).

10% is the standard of variation between bores. Both the dry and wet numbers are within this variance . . .

What has you worried?

regards,
stock49

Your pressure numbers seem reasonable and even, as already mentioned. If the engine is smoking, or burning oil, you need to find out whether it's from the worn cylinders/rings or valve stem seals.

In general terms.... The seals would leak oil into the combustion chamber especially at idle and deceleration, less during acceleration. Ring/cylinder leak works the opposite; smoking more under acceleration and higher rpms. If the engine doesn't smoke much when you come to a red light, and sit there waiting for the light to turn, but then puffs out a lot of smoke when you take off, that's likely the stem seals seeping through during high vacuum, then the pooling oil will get burned quickly as you accelerate and airflow through the engine rapidly increases (as well as exhaust manifold temperature).
Not sure how well this applies to your engine.

194 engine on frame no real load

Smokes some on initial start
Heaviest smoke on rev after prolonged idle.
Steady low cruise rpm very little if any smoke
Steady high cruise rpm hint of more smoke than low cruise
New plugs all show identical light even oil on threads, but the electrodes at the tip are clean of oil. No stand out member of the group.

Gonna do valve seals

I have run this engine on the frame in 2011, 2012 while waiting on body work completion and now in the first part of 2013. The engine has always been very well behaved never smoked or I would have done a more thorough job while i had it on the stand. the only thing I did differently after a regasket, was add 8 oz of Marvel Mystery Oil and clean the original PCV valve and clear the clogged PCV hose nipple on the manifold. After 3 run periods totaling 45 minutes on new oil and MMO, the six began smoking on rev after idle.

Drained the oil and it looked like coffee. I Didn't intend to "flush" the engine, but MMO obviously has strong solvent properties. Had a couple of run periods since with fresh oil but it appears the smoke is hear to stay. The engine has 35K miles on a re-ring done a very long time ago, it just has had very little run time over the years.

I hope to see no problems when I pull the head.

Thanks for the replies