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 Exhaust manifold bolts gone.. 
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Post Exhaust manifold bolts gone..
So my Briggs EFI vibrated both bolts out of the exhaust on the right hand sod. Has anyone us d Stage 8 fasteners on a Briggs? Stage 8 (not grade 8) works great on hot rod exhausts.


Tue Jul 10, 2018 12:28 pm
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Post Re: Exhaust manifold bolts gone..
180" pounds is the Torque spec on the bolts. One main contributor to bolts backing out is an unbalanced propeller. You would be surprised at some New in box propellers are out of balance.

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Wed Jul 11, 2018 6:34 am
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Post Re: Exhaust manifold bolts gone..
Stage 8 bolts


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Wed Jul 11, 2018 6:39 am
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Post Re: Exhaust manifold bolts gone..
Check your prop and make sure the bolts stay tight after you correct the torque. I haven't seen a need for locking fasteners. proper torque is fine.

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Wed Jul 11, 2018 6:44 am
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Post Re: Exhaust manifold bolts gone..
I use these, no problems Image


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Wed Jul 11, 2018 11:36 pm
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Post Re: Exhaust manifold bolts gone..
Couldn't get pics to load on mmt anymore so had to get tapatalk. The pics are a little bigger than normal, lol


Wed Jul 11, 2018 11:50 pm
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Post Re: Exhaust manifold bolts gone..
The only thing that sucks about a stainless bolt.... Is when it breaks/ galls inside the head....BRUH its hard as a MFER to get out..

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Thu Jul 12, 2018 5:41 am
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Post Re: Exhaust manifold bolts gone..
Why not install studs and use locking nuts ? Never had one come loose again.


Thu Jul 12, 2018 6:03 am
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Post Re: Exhaust manifold bolts gone..
MaXXis85 wrote:
The only thing that sucks about a stainless bolt.... Is when it breaks/ galls inside the head....BRUH its hard as a MFER to get out..

You are right about that possibility. So far none have broken. The hardest ones for me so far have been broken off steel bolts. I'm hesitant to use antiseize on steel bolts because I like the friction to keep it from backing out. With theses I use plenty of lube and rely on the spring tension of the locks. I get creative with a welder to get broke ones out. Even had to weld up holes and start over. Knock on wood I've saved them all


Thu Jul 12, 2018 9:20 am
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Post Re: Exhaust manifold bolts gone..
I keep extra bolts in the boat. I always neverseize the heck out of the bolts when I put them on.

I go through at least one muffler a year, most years 2. stock mufflers suck.
vibrations from out of balance props or something amiss in your driveline will cause all kinds of things to shake loose/break.

if u have axcess to those fancy bolts, use them and let us know how they do.


Sat Jul 14, 2018 1:10 pm
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Post Re: Exhaust manifold bolts gone..
I need to order some bolts for my exhaust too. What size are they?


Thu Aug 02, 2018 11:14 am
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Post Re: Exhaust manifold bolts gone..
8 x 1.25 metric thread


Thu Aug 02, 2018 12:01 pm
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Post Re: Exhaust manifold bolts gone..
Will C wrote:
8 x 1.25 metric thread


do you know the length?


Fri Aug 03, 2018 8:23 pm
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Post Re: Exhaust manifold bolts gone..
Ducknut wrote:
Will C wrote:
8 x 1.25 metric thread


do you know the length?

Stock is 25 mm. thicker flanges need thicker bolts.

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Mon Aug 06, 2018 5:24 am
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