Thread: ? needing to re-ring one piston

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have a rebuilt 327 (9: 1 cast piston, chrome rings), since rebuilt, which now has 6,000, the # 1 cylinder has always been low on pressure, rest are fine on pressure. (sounds stupid, but I am second guessing myself thinking I must have put a ring in upside down or something) anyway I am going to pull the heads and check every thing out, barring don't see anything obvious. I am going to re ring that piston with a new rings. should I put a new bearing in on the rod, or just reuse the one that is in there, since there is only 6,000 miles on it? also should I hone the cylinder ? what could keep one piston from setting?

Don't be so sure it's the ring's in that Cylinder . More times then not its a valve not seating well . This is why I hand Lap all my valves to the seats . Did you try some oil in that cylinder and then Do the C/R Test ?

did do a leakdowm test with 100psi of air on a warm motor, tdc, was blowing into the oil pan. tore the block down, piston had oil on it, every thing on piston "look's" o.k.??? putting new rings on it, honed the cylinder. will post back afther firing it back up. has anyone ever heard of one piston not seating afther a rebuild???

how did you hone the cylinder?

well chrome rings are not user friendly as for lapping valves i do not do it all the time my valve jobs are good with or with out if them valves are not sealing at 6000 miles i would say thats a very bad valve job i lap them to cut the back angle if i am going to do that

Is this 327 a fresh re-bore +030 ? If not you should run Cast or Moly Rings .

i used cast rings, the engine was built in 94, since then I have only put 6,000 mile totaL on it. I used a hone tool you use with a drill( 320 grit)

well guys, gotit back together, fired it up, broke it in (rings) runing great, think it is running better than it ever has, idles so much better, power seems to have doubled. so i think it fixed the problem!!!! just hope it is a perminate one.