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View Full Version : HELP! 2.4 Bridgeport Carb 2nd time scuffing #5 cylinder



Shmitee
04-28-2001, 06:40 PM
Noticed low compression in #5 cylinder (99 p.s.i.). Took a closer look and piston was scuffing cylinder wall. Did total rebuild (sleeved #5, new pistons, new rings, new bearings and put a bigger jet in the #5 carb). Broke the motor in for about 8 hours not going over 4000 r.p.m.'s and running 35:1 oil. Ran motor for about another 8 to 10 hours with 50:1 oil and still took it easy. After that made a few speed runs to see what it would do and I noticed I wasn't getting the R's that it used to with the same prop. I took another compression test to see what was happening and #5 was low again around 99 p.s.i. Took a look inside and the piston is scuffing the cylinder wall the same as before. What could be making this happen??? Could a bad stator cause this? Any input would be greatly appreciated!!

Thanks !!!

MERCMAN
04-29-2001, 12:44 AM
COULD BE A FEW THINGS. YOU COULD HAVE TRASH IN THE CARB SOMEWHERE OR THE SLEEVE JOB MAY NOT HAVE HAD ENOUGH CLEARANCE FOR THE NEW PISTON. WHAT KIND OF PISTON DID YOU USE? BRIDGEPORTS ARE VERY FICKLE ABOUT A SLEEVE JOB. THEY HAVE TO BE RIGHT , NO ROOM FOR MISTAKES IN THAT BLOCK.

MTCM
04-29-2001, 07:48 AM
I am no expert. I have had some experience with reciprocating compressors. I have seen piston rods that were not true cause scuffing in cylinders. You cannot tell by just looking at them sometimes. Hope you find out problem.

MTCM

jimmyb
04-29-2001, 09:22 AM
ditto what mercman said...

i would also recommend that you go with a piston/liner combination that you know works (talk to others that have had it done). Piston profiles are extremely complex... if you dont have the right combination, then things wont work right

did you have a steel liner installed? what kind of piston did you have installed?