Piston ring order
 

I made the mistake of getting ahead of myself and taking all of the rings off of my pistons for cleaning. I kept them with there respective pistons but failed to mark the placement. The oil ring is obvious and the compression rings are marked for top but what is the difference between the two top rings? In the book it states that they are different but not how. And if they are, how can I tell them apart and what one should be on top? They are from a new set of Pistons & Cylinders from Mahle.

There's a bevel on the top ring that drives it outwards against the wall. Off the top of my head (95% sure), the bevel should be angled so that the beveled edge is towards the top of the piston. The ring under it should be the opposite?

I'm 95% sure of this, but I don't have my references in front of me right now...

-Wayne

Wayne,
What you siad makes sense but after looking at the rings here is what I have found. All of the compression rings are marked the same as follows "GOE 6" & "TOP 3 IKA". The bevel on both rings would be in the same direction unless I installed one up-side-down. Any chance you could pull a new set off the shelf at pelican and see how the rings come from the factory?

The top compression ring is not as thick/tall as the middle compression ring. Measure the two, and this should tell you which one goes where.

The two top rings are identical as far as i can tell. Is there any chance that they not correct? They came preinstalled on a set of pistons from Pelican Parts. I really hate to install them just to find out that the motor needs to come back apart. Any help would be great.

Use a caliper and measure the "height" of each ring. If I remember correctly (again, no reference material with me) Jay is dead on. I also think there is enough difference in the SC pistons (I do not know the rest) that you cannot install the thicker one on the wrong slot.

any printing on the ring denotes the top.

The rings are clearly marked "top". The question I have is if there is/should be a difference between the 1st and second ring? Both rings appear to be identical but I have been told that they should be different. I will be putting the rest of the pistond and cylinders togeather this weekend so I want to be sure that it is correct. Any help would great.

Thanks in advance,
Bill

Bill,

Did you follow Jay's and my advice on how to measure and which goes on top?

any inside bevel goes up. the top ring is stiffer than the second one. you can tell when you install them.

Right - Jay is spot on - why don't you measure them with your calipers?

-Wayne

They both measure the same. I am really at a loss here as everyone confirms that they should be different but they are not. Could they be the wrong rings?

What is the year of your car...I'm assuming it's a 930 from your user name?? Do you have the factory spec books? Maybe someone can get the specs for your rings if you provide more info on your engine.

It is a 1977 930 with a 930/50 engine. The problem is that I am installing a new set of 3.2L (big bore kit) P&C's that I purchased from pelican. The factory spec book wont help I am afraid. I wish I could have someone pull a set of these and check the rings to be sure they are correct. Looking and measuring the 2 compression rings they are exactly the same in every way (design, markings, size). Everyone is telling me they should be different. I am at a loss here.... I will be installing these on friday morning so I really need to find this out.

If they measure the same, then they should be the same then...

-Wayne

The P&C's are installed. Thank you everyone for your help.