How do you know if the piston rings are bad (Spree)?

Animal Chin · Post by **Animal Chin** » Tue Aug 12, 2008 9:10 pm

Hello,

I was wondering what the signs are of bad piston rings. I was running my Spree at full throttle when there was a loud backfire and a very strange smell. Although it turns over, it won't come close to starting. I checked and it is getting a spark and I feel air coming out of the muffler. The strange thing is that it sounds like the piston is moving too fast when I try to start it (the type of sound you hear when there is no spark plug in the engine). I assume this means that I am not getting compression and the rings are screwed. I would appreciate any input you guy have before I order some new rings (I just put new rings on 2 months ago!). Thanks.

justinnielsen01 · Post by **justinnielsen01** » Tue Aug 12, 2008 10:19 pm

check reeds first if its not that then get some ring for it from http://www.cheapcycleparts.com

Kenny_McCormic · Post by **Kenny_McCormic** » Wed Aug 13, 2008 12:18 am

Pull the top end apart ans see whats up.

-aL- · Post by **-aL-** » Thu Aug 14, 2008 2:10 am

Or do a compression test. Could be a bad gasket somewhere. Maybe something cracked.

Clivester · Post by **Clivester** » Thu Aug 14, 2008 12:24 pm

If you are checking the compression, an old mechanics trick:

Add about 1 teaspoon of (2-stroke) oil through the plug hole. Turn the crank a couple of times to distribute the oil, then retry the compression check. After doing the check turn over the engine with a few times with a rag in the plug hole to remove excess oil.

If your compression goes up into a decent range with the oil its almost certain to be worn rings that are the problem rather than broken rings, cracked head or leaking gaskets.

Clive.

Kenny_McCormic · Post by **Kenny_McCormic** » Thu Aug 14, 2008 1:06 pm

Clivester wrote:If you are checking the compression, an old mechanics trick:

Add about 1 teaspoon of (2-stroke) oil through the plug hole. Turn the crank a couple of times to distribute the oil, then retry the compression check. After doing the check turn over the engine with a few times with a rag in the plug hole to remove excess oil.

If your compression goes up into a decent range with the oil its almost certain to be worn rings that are the problem rather than broken rings, cracked head or leaking gaskets.

Clive.

Sometimes its form overheating and the rings stick to the piston, sometimes the oil boosts compression enough to get it running and things fix themselves from there.

Animal Chin · Post by **Animal Chin** » Fri Aug 15, 2008 11:36 am

I took the engine apart and nothing really stuck out to me as an obvious problem (of course I don't really know what it is suppose to look like). There was a huge scratch on the piston and small pieces of metal or something on the head. The rings looked fine to me so I don't know where the metal pieces are coming from. The piston also did not have any breaks that I could see. I am assuming that the scratch in the piston is a problem so I will be ordering another piston. Is it possible to reuse the piston rings or should I replace them also. Thanks for all your responses.

Clivester · Post by **Clivester** » Fri Aug 15, 2008 12:40 pm

You should definitely use new rings in that sort of situation. Also do your absolute best to figure out where that metal is coming from. You don't want to go to the trouble of fixing everything only to have it all happen again. Are both the clips still on each side of the pin?

Don't forget to re-hone the cylinder.

Clive.

Kenny_McCormic · Post by **Kenny_McCormic** » Fri Aug 15, 2008 2:34 pm

Whats the bore look like?

Animal Chin · Post by **Animal Chin** » Fri Aug 15, 2008 4:26 pm

The cylinder has a scratch in it but it is not real deep. It is however deep enough to be felt by rubbing your finger on the cylinder.

p.s. I hope cylinder and bore are the same thing

Kenny_McCormic · Post by **Kenny_McCormic** » Fri Aug 15, 2008 4:52 pm

They are, you should hone that out.