labrat Posted June 13, 2002 Share Posted June 13, 2002 Well, i finally figured out my oil consumption/blowby problem. Pulled my 350 last night and tore it down this morning, and found 5 broken rings. The top ring seemed to give right about in the middle (although one broke into 4 pieces)... At least they didn't score my cylinder walls. My question is, what could have caused this? I'm thinking it was either improper ring gap, or just crap building up in the ring groove, but before I reassemble this thing, is there anything else I should look for? I don't want this happening again... Bill Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted June 14, 2002 Share Posted June 14, 2002 Improper end gap, yes; but a quick fit of detonation from being too lean or too much timing advance will break a ring like that. Quote Link to comment Share on other sites More sharing options...
labrat Posted June 14, 2002 Author Share Posted June 14, 2002 Thanks, that's entirely possible. I rebuilt the carb right before this happened, and had problems getting the gasket to seal on my spacer... that makes sense now. I was just trying to avoid going through this again... Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted June 14, 2002 Share Posted June 14, 2002 Good call, I'd say detonation as well. There are alot of shockwaves sent through the chamber when the mixture explodes instead of a controlled burn like its supposed to. Hammer sideways on a ring and I'm sure it'll crack rings right before it takes the ring lands out. Regards, Lone Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted June 15, 2002 Share Posted June 15, 2002 That was something I should have mentioned. Give the land areas of the pistons a good inspection to make sure they didn't get damaged as well. Thanks Lone. Quote Link to comment Share on other sites More sharing options...
labrat Posted June 15, 2002 Author Share Posted June 15, 2002 Well, i didn't drive it too far when this happened before the beast got parked (just a few miles), as at the same time I bent a few pushrods... I thought i had tightened them down too tight when i replaced the head gaskets, but the detonation explanation is making more sense. The lands on the piston look okay, still nice and flat, but damn are those rings tore up! Good thing I pulled the motor and tore it apart, instead of trying to keep it running this way. Oh well, now I at least know I have a 4 bolt main with a nice balanced rotating assembly and chamfered oil holes on the crank with new clevite bearings and new rings. Now I just need a new cam and heads and i'm in business... Quote Link to comment Share on other sites More sharing options...
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