1987 40 hp Johnson problems

mike carson

Cadet
Joined
Aug 13, 2012
Messages
14
Need to pull the flywheel off to do a tune up what size is the bolt holes and are they standard or metric for the pulley puller? By the way thanks for all of the help I have gotten from everyone.
 

Daviet

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Sep 24, 2008
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8,958
Re: 1987 40 hp Johnson problems

Standard thread, 1/4 x 20, make sure and use grade 8 bolts.
 

mike carson

Cadet
Joined
Aug 13, 2012
Messages
14
Re: 1987 40 hp Johnson problems

Thanks buddy and I'll make sure they are # 8

I have tried 5/16 20 # 8 it starts easy but get real tight only after a few threads even when trying tap. Tried what you said using 1/4 bolts but they were to small could the holes be metric.
 

boobie

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Nov 5, 2009
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20,826
Re: 1987 40 hp Johnson problems

Are you sure you have 1/4 x 20 bolts and not metric ones ??
 

mike carson

Cadet
Joined
Aug 13, 2012
Messages
14
Re: 1987 40 hp Johnson problems

Yep i don't understand it 1/2 slides up and down falls in the holes and 5/16 and they are very tight i dont want to mess up the holes or snap the bolt off in the flywheel any ideas.....
 

Daviet

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Sep 24, 2008
Messages
8,958
Re: 1987 40 hp Johnson problems

My set has a 5/16 x 24, fine thread, I have never used it but it is there. Maybe I was wrong about the size.
 

boobie

Supreme Mariner
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Nov 5, 2009
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20,826
Re: 1987 40 hp Johnson problems

I think it takes the 5/16-24 bolt now that you mention it.
 
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