Broken ring lands???

[turbov6joe]

If a ring land was broken, would/could a compression test still come back fine on that particular cylinder? What damage would this broken land cause to the motor??

 

[Nick Micale]

Compression should be down a little, sometimes not very much. It could score the cylinder wall enough to require a sleeve.

As you may guess, this is not an opinion but based upon fact! [Unfortunately, seen it a couple times.]

 

[cool 84]

I have one experience with this. What was weird is I was just cruising at a steady speed, almost home and it just dropped a cylinder.

I had broken the ringland between the top and second rings. It stayed in place and didn't hurt the cylinder or anything but when I pulled the motor apart, 1/3 of the ringland fell to the ground. I never did a compression test but it would have to be nearly 0. While cranking I could hear the dead cylinder, the starter would speed up everytime it hit that particular one. Since the motor was junk, I raced my friend's V6 Mustang right before I shut it down for good. It was close at first but once it hit 10psi the dead cylinder came to life again and it ran almost as strong as before. It's weird how fast it can blow most of the oil out of the breather hole. Pistons were TRW forged if it matters and were set up WAY too loose by the builder.

 

[Chuck Leeper]

Set up too loose??

Damn, Jason's at it again!!
And I was under the impression he was/is "MR TURBO" on the hi desert!!!

 

[bruce]

Originally posted by turbov6joe
If a ring land was broken, would/could a compression test still come back fine on that particular cylinder? What damage would this broken land cause to the motor??

If it was the top ring, leaving bits might hold the exhaust valve open enough for the piston to smack it.
Chunks of it going thru the turbo would be a bummer.
Possibly travel up back past the intake valve and dance from cylinder to cylinder for a while.

Piston skirt could even be more fun.