Which Piston Rings Do You Use?

[kangaroosa]

Some of you may know that I have been having some oil consumption issues with my 5K. The motor is due to come out early next year to have a new set of rings fitted.

The engine builder told me that on each rebuild (about 4 within 12 months) he used Molly rings manufactured by Hastings. This rebuild we plan to use Chrome rings.

I have chrome rings in my old 4K which saw about 4 years of hell and still never used a drop of oil.

 

So i'm interested to see what brand and type of Piston rings you guys and gals have used, and had sucess with.

[TRD ke70]

why did he use moly rings???

this could explan why it's using oil.

 

 

i use cast rings only, found that chrome ones chew the hell out of the bore, they don't crack but if you ever strip the engine back down you'll find that you'll have to rebore it.

 

with cast rings, you have to make sure that you hone the bore correctly.

and don't use Castrol oil when you run it in, as it's friction modified and this will glaze the bore back up and you'll start using oil again.

 

basicly cast wear the ring, chrome wear the bore.

[Teddy]

^^ 20 or so years of testing = an answer like that :D

[kangaroosa]

why did he use moly rings???

this could explan why it's using oil.

i use cast rings only, found that chrome ones chew the hell out of the bore, they don't crack but if you ever strip the engine back down you'll find that you'll have to rebore it.

 

with cast rings, you have to make sure that you hone the bore correctly.

and don't use Castrol oil when you run it in, as it's friction modified and this will glaze the bore back up and you'll start using oil again.

 

basicly cast wear the ring, chrome wear the bore.

 

No Idea why he used Molly. I have Hypertec pistons.......would it be anything specific to do with that?

I assume that molly is not the most preferable choice. For my curiosity, why would the Molly rings be causing me so many dramas?

 

So do you have a preferred brand of rings that you use?

I hear Hastings (the ones i have) are good. But maybe i should try the Cast versions of them.

[TRD ke70]

i was thinking that with a moly ring you have to have a very fine hone on the bore and this can cause problems with the ring not bedding in, so you end up with the bore glazed up.

 

in your engine i'd use just a cast ring with a good hone, around 400 grit.

when i hone the bore i use carby cleaner to get as much oil off the cylinder walls as possible, also makes the honing stone bite in better. i also don't oil the rings when fitting them.

 

Hastings rings are good, i've used Pro Tec and there good too.

Grants are another brand, but i've had mixed results with them.

i doesn't matter what pistons you have in your engine.there's no set rule for what rings you use with what pistons.

 

the biggest things for me are, the hone on the bore, the oil used when running in and how the engine is run in.

here's a link from an old post, have a read, it'll give you an idea of what you're needing to do.

 

running in

[Felix]

couldn't be a problem with bore flexure at hi RPM's? weren't they 82mm gemini pistons?

 

i'd be looking for a new engine builder myself.

[kangaroosa]

couldn't be a problem with bore flexure at hi RPM's? weren't they 82mm gemini pistons?

 

i'd be looking for a new engine builder myself.

 

Yep 82mm pistons. I don't rev my engines much at all. Infact it rarely sees 6000rpm. Its used oil from day one, so i doubt its due to high RPM associated issues.

 

This engine builder is going to keep doing it until he gets it right.