piston rings maybe

[TOPTON]

Not my S2 thankfully. My sons 1.5Lsi civic was blowing loads of blue smoke out the tail pipe. Two possible answers-valve stem seals or piston rings. Got the engine striped out now. I remember something about putting WD40 or the like in the bores to see if it soaks away to check if the rings are worn. Does this sound correct? Maybe I am remembering something totally wrong. Thoughts would be appreciated..T

[Tank Slapper]

How far have you stripped it? If you haven't taken the head off yet, do a compression check and compare against the book figures. If the pressures are low, squirting a small amount of oil into the cylinder may give a temporary increase in pressure and would indicate that the rings are worn. If there is no change then the problem is likely to be top end.

[TOPTON]

I have the engine totally striped, apart from the crank, con rods & pistons. Should have done a compression test before hand but was confident it was the rings. Now not sure. Not much extra work stripping them out, just extra money getting replacement if not needed.

[Tank Slapper]

As you have it that far stripped you might as well have a look at the bearings and rings, and possibly change them - at least you know you have a good bottom end then. The extra time would be worth it to make sure. I doubt that the parts would cost too much.

If you can, measure the bores for wear - it would be a waste to put it all back together and find you still have problems.