Main Bearing trouble.
#11
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numbers 1 and 3 again some small scratches from banging into each other in the bag...they look black in this picture but it is mostly due to the lighting...they are that dark brownish color ...they were that color new.
#12
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and the thrust bearing...note the scratch that exposes copper near the edge...I am thinking a piece of dirt/ debris maybe?Unless I knicked the crank and didn't know it..that's a possibility I guess.
#15
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Looking at the bearings I would say either your crank or main bearing bores are tapered,maybe both.have someone with a tenth reading bore gage check your main bearing bores for taper and then measure the crank.Bill
#16
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Originally Posted by billhendren
Looking at the bearings I would say either your crank or main bearing bores are tapered,maybe both.have someone with a tenth reading bore gage check your main bearing bores for taper and then measure the crank.Bill
Just a question..how does a brand new block end up with taper on the main bores? The crank I can understand but how does a block get line bored tapered? Not arguing just asking.
#18
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My Eagle crank was all screwed up right out the box.Journals were kinda crescent sheped.High in the middle,low at the radius'.Is there any such thing as truly "machined" parts straight out the box???
#19
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MINE WAS FROM OHIO CRANKSHAFT.
Like I said I mic'ed it but only in the center. He said the balance was close enough for a street engine but not if it was being ran hard.
Don't know anything about balancing and bob weight but what he said was he only had to over balance it I think 10 grams in the rear to make it right...said he just needed to drill a hole or something and it would be right...so I doubt that was my problem. Sounds like it was pretty close. I forgot to ask about taper I was half asleep when he called(I work nights)
Like I said I mic'ed it but only in the center. He said the balance was close enough for a street engine but not if it was being ran hard.
Don't know anything about balancing and bob weight but what he said was he only had to over balance it I think 10 grams in the rear to make it right...said he just needed to drill a hole or something and it would be right...so I doubt that was my problem. Sounds like it was pretty close. I forgot to ask about taper I was half asleep when he called(I work nights)
#20
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The most common problem when you find taper in the block is foreign material like chips under the cap when it was align honed. Taper in the crank journal is far more common with the crank you have and thats what it looks like on the bearings.make sure someone measures the crank carefully for taper AND out of round or you will end up with the same problem.Bill