Can you reuse bolts

Stryped

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I am rebuilding a 49 series v twin 27hp that broke a rod. Can the head bolts and rod bolts be reused? Or are they torque to yield?
Can regular grade 8 bolts be used instead?
 

Rivets

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I’ve never had a problem reusing head bolts. Just make sure they are clean and dry before installing. New rod should come with new bolts.
 

Tinkerer200

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I have reused bolts for 65 years, no problem except I did buy new grade 8 bolts from local farm supply store when installing new sump gasket in V Twin B&S because of greatly increased torque spec. due to chronic sump gasket leaks with 40 and 44 series engines.
Walt Conner
 

ILENGINE

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I’ve never had a problem reusing head bolts. Just make sure they are clean and dry before installing. New rod should come with new bolts.
The only time I haven't reused head bolts unless they came with a new head was on the old K series Kohlers. Something about the aluminum to cast transition would cause the head gasket to blow if you reused the bolts.
 

Stryped

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I’ve never had a problem reusing head bolts. Just make sure they are clean and dry before installing. New rod should come with new bolts.
It’s a used rod I am using
 

Stryped

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I have reused bolts for 65 years, no problem except I did buy new grade 8 bolts from local farm supply store when installing new sump gasket in V Twin B&S because of greatly increased torque spec. due to chronic sump gasket leaks with 40 and 44 series engines.
Walt Conner
This is the problem this engine had. The factory sump bolts are fully threaded. Did you use partially threaded bolts from the farm store?
 

Stryped

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I have reused bolts for 65 years, no problem except I did buy new grade 8 bolts from local farm supply store when installing new sump gasket in V Twin B&S because of greatly increased torque spec. due to chronic sump gasket leaks with 40 and 44 series engines.
Walt Conner
Did the torque spec change? What was it?
 

Stryped

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I’ve never had a problem reusing head bolts. Just make sure they are clean and dry before installing. New rod should come with new bolts.
I thought some type of lock tight was supposed to be used?
 

Walt 2002

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It was 4 years or more ago that I bought grade 8s from Rural King, I don't remember for sure but I do not believe they were fully threaded but as far as was needed.

I am 89 and have not worked on engines for a few years but I think original torque was 120 inch lbs. and went to 200 inch lbs when they introduced their "fix" kit which was $35 - $40 last I knew. Thoroughly discussed with that outrageous price, I made my own gasket, bought new grade 8s and torqued to new setting, no problems so far.
Walt Conner
 

Rivets

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No Loctite, and most head bolts are grade five, partially threaded. Just make sure they are clean, dry and in good condition. Also make sure the holes are clean and dry.
 
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