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View Full Version : 75 searay with 87 jasper ford 302



jeremy421
04-21-2006, 01:52 AM
"hello all, i am new here and impressed with the discussions. TY to the founders!!! i have a 1975 searay that i picked up with a shot motor, replaced it with a Jasper rebuild and now with less than 500 hours on the newly rebuilt motor the thrust bearing has gone out and of course taken the crank with it. My first question is "WHY?". the front side of the bearing has close to no ware but the back side is destroyed along with the crank where it touches the back side of the #3 main (thrust). It appears as if something was constantly trying to push the crank out of the front of the motor, i know a deformed torque converter will do this to a crank.. but the last time i checked a boat has no torque converter. Any help would be appreciated. OH... the main and rod bearings have definitly been hot (as if lack of lubrication [even though it always had plenty]), however the cam and it's bearings look great. Thanx again; Jeremy"

fastjeff
04-21-2006, 07:27 PM
Jeremy:

The other bearings getting hot is related to the thrust bearing burning up on you.

Why did that happen? Darn good question. All I can think of is that the tranny was pushing like crazy against the crank when it was installed--sort of a mis-match there. I'd be extra careful when you put everything back to make sure there's some end play.

Jeff

jeremy421
04-22-2006, 09:14 PM
"Thanx Jeff, this may be the issue, i don't remember actually checking that when i first installed this motor but i can't imagine not checking it either.
It's the same motor just an 87 rather then a 75, and the mounts were not moved. I would like to pinpoint "why" so that i can avoid having the same problem again. Motors are not cheap. At any rate i will make sure that i remember to check that this time.
Thanx again and if anybody thinks of anything else please let me know."