1989 150hp Yamaha head bolt torque?

[Asainz320]

I did a search and i found that its supposed to be 22 lbs. Is that corect? That feels so weak when im torquing the bolts, i feel its not sealing right. What happens if i torque it lets say to 40lbs ?

 

[rodbolt]

Re: 1989 150hp Yamaha head bolt torque?

22 worked for years and years.
at 40? you will be posting about broken 8mm bolts and pulled threads from the block. why ya gotta re-engineer a known good product?
make sure every thing is cleaned,tapped holes have been chased,bolt threads cleaned and coated with pipe sealant,. and assemble it correctly.
its so easy a cave man could do it.

 

[Ray Neudecker]

Re: 1989 150hp Yamaha head bolt torque?

Right at 30 lbs is when the head bolts break or pull the threads.

 

[Asainz320]

Re: 1989 150hp Yamaha head bolt torque?

Ok guys thanks a lot for the advice, 22 lbs it is then. Another question. Should i use silicone on the head gasket? I bought a gray silicone at the auto parts and it says it is for high temperature and designed for torque. It has a rating to withstand 650? F. Will that work if i put it between the gasket and the block on both sides? Thanks

 

[rodbolt]

Re: 1989 150hp Yamaha head bolt torque?

no no no
the best thing you can do with that silly cone is walk to the bow and throw it as hard as you can. it has no place on the yamaha.
its really not even good to seal the transom mounting bolts.
if you have to use something then BRP gsketmaker or quicksilver perfect seal will work. but the OEM gaskets come with a heat activated sealer already on the gasket.
biggest thing is surface cleanliness NO WIRE BRUSHES, and surface flatness. it MUST be checked.
why are you trying so hard to re-engineer a decent product ?

 

[Asainz320]

Re: 1989 150hp Yamaha head bolt torque?

lol im not trying to re-engineer the product, im just asking so i dont make a stupid mistake later. Once again, thanks a lot for your advice rodbolt.

 

[BigBand]

Re: 1989 150hp Yamaha head bolt torque?

Why not use a wire brush to clean off the old gasket material?

no no no
the best thing you can do with that silly cone is walk to the bow and throw it as hard as you can. it has no place on the yamaha.
its really not even good to seal the transom mounting bolts.
if you have to use something then BRP gsketmaker or quicksilver perfect seal will work. but the OEM gaskets come with a heat activated sealer already on the gasket.
biggest thing is surface cleanliness NO WIRE BRUSHES, and surface flatness. it MUST be checked.
why are you trying so hard to re-engineer a decent product ?