Question about car with stuck Piston Ring

[ebaker]

It seems likely it's been overheated and the rings lost their spring tension. I don't think a single ring getting "stuck" is that common.

 

[good2go]

ok. how much should compression be with a stuck ring? with a cracked ring?

when i pull the dipstick am ilooking for smoke coming out of it? if there is no puffing smoke coming out of it that means the compression rings are ok, but the oil ring is shot?

 

[good2go]

can the oil ring stick or is it just shot?

 

[Rickey]

If there is oil smoke out the exhaust but no blowby out the dipstick (I would prefer a check by removing the PCV valve as the PCV system can eat a small amount of blowby) then the oil ring(s) and/or valveguides are suspect. Also there is the possibility of oil being sucked into the intake manifold possibly even through the PCV valve. What does the smoke from the exhaust look like? If it's blue it is indeed from oil burning. However black smoke usually indicates an overly rich mixture from too much fuel. White smoke would be coolant entering the combustion process. The exception is that white smoke can also come from misfiring plug(s). Blowby (from the crankcase) usually has a grey appearance. However any appreciable volume of anything (even without coloration) being blown from the crankcase out the dipstick or PCV openings would be suspicious. Also look out for the motor oil being diluted with fuel as this can cause poor ring sealing, smoking, and blowby. If the rings are suspected to be stuck (blowby): an aggressive solvent such as Berrymans B12 chemtool or Seafoam may be used. The proceedure I use is thus: 1 Warm the engine. 2 Put on a new (cheap) oil filter to catch the debris that will be hopefully be flushed out. 3 Add a container of oil thickener (STP or similar) to the oil. This is done because the solvent to be used will thin the oil a lot when it drains past the rings. 4 Briefly run the engine to mix the oil thickener. 5 When cool enough remove the spark plugs. 6 Pour approximatey equal amounts (divide a whole can between the cylinders) of solvent in the spark plug holes. A funnel and suitably sized hose may be useful here.7 After 1/2 hour or so repeat solvent application. 8 After another 1/2 hour or so pour a small amount of motor oil (a teaspoon or less) into each spark plug hole. This is done for lubrication as you have just washed most of the oil from the pistons, rings etc. 9 Replace spark plugs and crank the engine. Use enough throttle to clear it out (till it runs smoothly). It will smoke a lot until the oil and solvent is burned off. Then let it idle until thoroughly warmed up. 10 Change the oil and filter. Disclaimer: I have used this on several engines in the past. A few were helped greatly, some showed no improvement (problems other than stuck rings), none were damaged. But I suppose it is possible to obtain damage by this method as it is rather aggresive. You might want to skip step 7. Also note that as mentioned by another poster: Stuck rings arn't all that common. Damage from overheating is probably more likely. Or it may just be worn out(use oil thickener for this). Of course you don't know 'till ya know. Hope this is helpful. Good luck. Rickey

 

[good2go]

thanks guys for all the replies, they were very helpful and i will use them in the future for sure, but unfortunetly, the car was sold last nite before i had a chance to look at it today.

thanks for all you very apprciated help!-

-Neil

 

[Eddie]

Purchase the vehicle and reduce the price ( book price) by the cost of 1/2 a complete re-ring job at a local shop. ed