Adjusting oiler (third) piston ring...how do I 'bend the tabs'

CaifanSC

SCCoA Member
I got a 30 oversized set of rings for my 20 bored block. top and second are gapped already, just need to ADJUST the third ring, the oiler ring, to fit properly. The manual sais to 'bend the tabs', but im not exactly clear on what this means. Any help is appreciated.
 
There's no bending of tabs so dont worry about that. Just check them and see if they're at an okay gap. Usually they are good.
 
I was talking to a friend of mine and i kinda cleared something up. THere are three 'rings' in that go in the last groove...two really thin rings and the 'squiggly' spacer. I was told that I do need to gap the two thin rings to specs, which i will do...however, the squiggly spacer is still too large to fit inside the cylinder bore w/o having it scratch. Thats what im having problems with. Any suggestions?
 
get the right set of rings? You are probably going to have a lot more friction with .030 rings in a .020 bore, but maybe not, I'm not really sure.

I actually have an extra set of .020 rings from my rebuild (went with TS rings). I would say that you can have them cheap but it will be a while before I get home to ship them out.
 
I didn't see that you had .030 rings in a .020 motor. Thats not the greatest decision because instead of it becoming a circle the ring turns into more of an oval shape. I guess you'll see when you get it running whether or not it works though.
 
Given that motors are measured to such very very small tollerances... i.e. 0.001 at times, and that 20 over and 30 over are measurements of 0.020 and 0.030 of an inch respectively, you could look at it as going 10% over the required size.

We would probably need to know the manner in which those rings are formed in order to decide whether a bent ring will conform to the cylinder shape after intense heating as found in a running engine or not. If not, then get the right size ring.

Or, build as is, and after it's running, see if that particular sparkplug gets really dirty. ;) :D
 
CaifanSC said:
I was talking to a friend of mine and i kinda cleared something up. THere are three 'rings' in that go in the last groove...two really thin rings and the 'squiggly' spacer. I was told that I do need to gap the two thin rings to specs, which i will do...however, the squiggly spacer is still too large to fit inside the cylinder bore w/o having it scratch. Thats what im having problems with. Any suggestions?
you do realize that the "squiggly" ring goes in the groove first> then the others ontop and below the "squiggly" in the same groove. the thin rings will sit on the shelf of the "squiggly" ring. installed correctly they shouldn't scratch at all. good luck. check the ring end gaps for spec again before you button it all up cause when the engine warms up and the ends of the rings touch at all ,they will break and make a mess inside!! the point of using oversized rings is to minimize the gap for more compression . for a street car you will not really notice much differance and you set yourself up for some potential grief. be sure of what you are trying to accoomplish ,triple check everything and good luck!
 
CMac89 said:
I didn't see that you had .030 rings in a .020 motor. Thats not the greatest decision because instead of it becoming a circle the ring turns into more of an oval shape. I guess you'll see when you get it running whether or not it works though.
How do you get an oval shape out of that :confused:? The bore should be round which means there is extra stretch on the outside and scrunch on the inside. Since the bore will through use get larger at the bottom then the top, I see premature wear from the rings flexing in the tighter spaces but not misshape of the cyl. wall. Also, the rings spin (usually) when the engine is running. In the event they dont, I can see an unusual pattern on the cyl wall from scoring but oval? Please explain.

Chris
 
He is talking about the rings not being round since they are not the correct size for the bore. I never tried it but i would think the same thing, this is something you should be able to tell when you are fitting the rings to there bore.
 
seawalkersee said:
How do you get an oval shape out of that :confused:? The bore should be round which means there is extra stretch on the outside and scrunch on the inside. Since the bore will through use get larger at the bottom then the top, I see premature wear from the rings flexing in the tighter spaces but not misshape of the cyl. wall. Also, the rings spin (usually) when the engine is running. In the event they dont, I can see an unusual pattern on the cyl wall from scoring but oval? Please explain.

Chris
I didn't say the bore goes oval, I said if the ring is cut/filed to fit a smaller bore the piston ring will go past the circluar shape to an oval. I've already had this happen with another car.
 
I am not trying to challenge what you are saying so please dont take it that way but how to they go OVAL? Are you saying because you are opening the gap in order to smash them into a smaller bore that the brunt of the compression happens 180* out from the gap. Since they are larger then they should be this is the area that is stressed the most so they bend there causing an oval shape instead of getting full compression of the ring the proper way?

Chris
 
huckleberry said:
you do realize that the "squiggly" ring goes in the groove first> then the others ontop and below the "squiggly" in the same groove. the thin rings will sit on the shelf of the "squiggly" ring. installed correctly they shouldn't scratch at all. good luck. check the ring end gaps for spec again before you button it all up cause when the engine warms up and the ends of the rings touch at all ,they will break and make a mess inside!! the point of using oversized rings is to minimize the gap for more compression . for a street car you will not really notice much differance and you set yourself up for some potential grief. be sure of what you are trying to accoomplish ,triple check everything and good luck!

yessir, i was aware of that

As for using the bigger rings...i was told by the machine shop and by total seal that i should be fine. I was under the impression taht as long as you maintained your gaps correctly you are good to go.
 
Dont know how far I would believe that. If it were true, there would be one ring size that was file to fit for .010, .020, and .030 if you know what I mean.

Chris
 
True true...however, in my search i came upon various sites where filing of rings was perfectly fine, even several racing sites...thats why i was under the impression that the gap was whats important. Am i missing something?
 
I believe it is more of a racing thing because longevity does not matter in that situation. I still believe that it would work but if you can get the right ones...do it.

Chris
 
Chris, yeah im going to give it a try and see how it goes. IN any case, back to my question...in terms of 'adjusting' the squigly spacer...how do I go about doing that? And if beding one of the tabs is not enough to make it fit well inside the bore, can I cut one off?

I should be going out to my shed to continue work in a few hrs since its raining cats and dogs out here. Thanx! :)
 
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