What would cause dropped exhaust seats?
#1
Emerald Coast of Florida
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I dropped 2 exhaust seats #4 & #7 (#4 completely gone, #7 1/4 of it dropped out) on 2 different motors months apart. The motors are 502 GenV's only about 130 hours on them with Merc dual plane manifolds and Carter carbs, 088 heads. One dropped the seats last summer, so I replace it with a Gen6, 3 weeks ago other motor did the same thing. The motors ran fine, on start up the banging began. All the other pistons are black, valves also black, 4&7 valves are tan colored.
#2
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There were some 502's that had bad seat material ...I am not sure what version. I just had some heads reworked on a 98 502 MPI Mag and the seats were fine .....I'm sure someone will know ....m
#3
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I have seen to much cylinder temp cause them to come out and go threw the motor. If they fall out on start up of a new motor it sounds like they were not installed correctly. Which I have seen also.
John S.
John S.
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#5
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becoming a common problem.
Been blamed on fuel additives lately. Causing higher combustion temps
I know a few builders are upping the jet sizes to help the problem
Been blamed on fuel additives lately. Causing higher combustion temps
I know a few builders are upping the jet sizes to help the problem
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