Square Four Big-End 'Fillet' Radius - Clarification needed, please!

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allan.walker
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Square Four Big-End 'Fillet' Radius - Clarification needed, please!

Post by allan.walker »

I've taken two sets of crankshafts to an engine reconditioning firm to have the big ends and timing-side journals reground.

I thought that I had given them the correct information regarding the size of the radius on the ends of the journals, but having done a bit more reading-up on the subject, I think that I may be incorrect.
I told them that the radius of the fillet should be 3/16" (based on my recollection of seeing that quoted somewhere on this forum, but there is always the possibility that my memory is clouded........) The reason for my doubts is because Bruce Longman's instructions regarding fitting new conrods refers to the fillet being 3/32".

So, can anyone on here please confirm which is correct? (I don't like to keep phoning Bruce too many times...particularly at weekends!) In the past, I have measured fillets by using a drill bit, so in this case a 3/16" bit would have a radius of 3/32" and maybe this has given rise to my confusion.

Allan.
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chris.shearwood
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Re: Square Four Big-End 'Fillet' Radius - Clarification needed, please!

Post by chris.shearwood »

Allan,
It looks like it is 0.093" or 3/32" according to a crankshaft drawing I have.
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allan.walker
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Re: Square Four Big-End 'Fillet' Radius - Clarification needed, please!

Post by allan.walker »

Brilliant!
Thanks Chris.
Why would I have had any doubts whatsoever about what Bruce says....? I've given myself a slapped wrist. :oops:
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