500efi Saga Continues
#1
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500efi Saga Continues
So after replacing the entire valvetrain to get rid of lifter noise, upon removing engines this year for transom work; the rear exhaust valves are toasted. Heavily corroded looks like reversion. Engine has to come apart for the 3rd time. Anyone have issues with reversion on stock 500efi setup? Exhaust is cmi e top headers. They have been Pressure tested numerous times. No issues.
Before the rebuilds there was a lot of carbon build up but valves did not look like they look now. It's a stock cam, Johnson lifters, isky springs, scorpion 1.7 rockers, and trend push rods. Any help is appreciated. Thinking we may have to go dry to prevent this happening again. Going on 20k for top end rebuilds...should have left them alone.
Before the rebuilds there was a lot of carbon build up but valves did not look like they look now. It's a stock cam, Johnson lifters, isky springs, scorpion 1.7 rockers, and trend push rods. Any help is appreciated. Thinking we may have to go dry to prevent this happening again. Going on 20k for top end rebuilds...should have left them alone.
#2
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Are you running mufflers ??
#3
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#8
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Cylinder #8
https://i.imgur.com/qS4uLE7.jpg
Cylinder #2
https://i.imgur.com/uhJB95q.jpg
I think it's reversion because both motors are identical in terms of pattern. Rear cylinders are bad. Front of engine appear good.
https://i.imgur.com/qS4uLE7.jpg
Cylinder #2
https://i.imgur.com/uhJB95q.jpg
I think it's reversion because both motors are identical in terms of pattern. Rear cylinders are bad. Front of engine appear good.
Last edited by 1MOSES1; 11-06-2016 at 05:11 PM.
#9
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#8 is horrible. Yuk.
Rear cylinders primary tubes are the 'bottom' ones. Could be water leaks,,,,could be just the ignition timing. You pulled heads to get redone right ? Anything else touched other than removing heads, intake, dist, and exhaust ?
Rear cylinders primary tubes are the 'bottom' ones. Could be water leaks,,,,could be just the ignition timing. You pulled heads to get redone right ? Anything else touched other than removing heads, intake, dist, and exhaust ?
#10
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Lower end was not touched