Stretched piston rings and gap #s

psycho6cyl

Ponies Are For Lil Girls
Well starting.g to go back into car. Excessive blow by 50% on leak down going into pan, I pulled rings to check gap .016 top and .022 bottom. Put them back on piston and they seem really wide now. Can't remember if they were like that or not. I can basically take the ring off no problem for both. did I stretch them too far taking them off? Or do they get snadwhiched down once they go back into block?
150880287836334722035.jpg
 

750H.P.V6

Brutal 6 Racing
The ring effacement at the end gap is pretty high. The ring might have been over expanded when it was originally installed. The top ring appears to have a twist in it typically from someone spiraling the ring off the piston instead of using a ring expander. It can cause ring seal problems as it distorts the ring contact face. It might be worth replacing them for peace of mind.

Neal
 

ek02

Well-Known Member
If you have 50% leakdown, you need to check the cylinders for taper and out of round. New rings will not cure the problem if the cylinders are not round, it will make it worse.
 

Chuck Leeper

Toxic old bastard
Staff member
Looks like the ends of those rings were filed on a brick.:jawdrop:
Is the leak down past the rings, or the valves, or both?
 

Ttype6

Well-Known Member
I'm actually very done w this car.
No you're not. You've done the hardest part by starting the project and making it to the half way point. The rest should be enjoyable because it's going back together and the finish line gets closer every day and when it's over,you'll be able to say " I did it." The best part is that it doesn't have to be done today. Tomorrow is the best day ever invented to do just about anything.
Idk why the rings are shot.
What have you observed that led you to come to the conclusion that only the rings are the problem?
 

psycho6cyl

Ponies Are For Lil Girls
What have you observed that led you to come to the conclusion that only the rings are the problem?

Haven't observed anything to say it's rings. Was hoping it's rings and not a bore problem.

Car had lower compression on driver side bank. #5 cylinder being worse@140-145. Now it wasn't horrible. But lower than other. Pass side was better 175-180 all cyls. Leak down on #5 and it was 60% passing through into oil pan Thought it was head gasket replaced and redid leak down and it was now like 40-50% and this where I'm at..
 
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