Trying to finish 1/2 done projects. Got Briesch olds kit together, had running fairly well with home made rings,and heavy oiling seemed to have blowby, got new rings (3) from otto's at cabin fever 2003, installed and ran marginally better (with gas/naptha mix) but noticed oiler still getting foamed up from blow by? block is honed to 1.875, rings still witness od machined marks, but starting to burnish away, end gap at .006", groove gap was to tight as rings were starting to stick, but corrected. Is this one of those things where the more you run the better it is going to get? One person said that he made a piston "ringless" my piston is machined to 1.873 as per print, I just think that this engine should perform better. Its my first I.C. and pullin it out of the corner with my other 1/2 done projects, and hope to get'er done!!!!
Jeff Marx
Briesch olds kit
The oilers in the old engines had a check ball, in the base to pevent blow back. Most model engine types do not have the check ball. Got one from Debolt Machine and it has a check ball.
Starting out, getting rings to fit can be a problem. One thing I do is use a double seal o-ring, not cast iron rings. Seams to work fine, have engine that must have over 30 hours, of run time, with the same o-ring. Can get them at McMaster-Carr
Starting out, getting rings to fit can be a problem. One thing I do is use a double seal o-ring, not cast iron rings. Seams to work fine, have engine that must have over 30 hours, of run time, with the same o-ring. Can get them at McMaster-Carr
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pkastagehand
- Posts: 156
- Joined: Thu Nov 03, 2005 9:12 am
- Location: Holland MI
Breisch Lil' Brother
I've got a Lil' Brother that I built back in the late 70's. It doesn't even call for piston rings. I suspect my cylinder bore is not perfect and the first piston was a bit loose in the bore. Only time I've been able to get it to run was when I tried an O-ring. All I had was the hardware store variety and it seemed to get soft which increased friction as the engine warmed up and then it would stop. I tried to get a CI ring on it and broke the ring. Couldn't get it to flex enough to get over the OD of the piston.
Could you give more info on the "double seal" o-ring you mentioned from McMaster to help narrow the search?
Or tips, anyone, for getting piston rings on without breaking them?
Or should I maybe lap the cylinder to clean it up then fit a new piston with tighter tolerance?
Could you give more info on the "double seal" o-ring you mentioned from McMaster to help narrow the search?
Or tips, anyone, for getting piston rings on without breaking them?
Or should I maybe lap the cylinder to clean it up then fit a new piston with tighter tolerance?