Block threads stripped...

Zack19919853

Seaman
Joined
Aug 17, 2019
Messages
74
As I was torquing down the head bolts to 20 foot pounds, which is what I read on another post, is this correcet? Anyway, six bolt on the port side started to get loose so I backed it out and found threading on the bolt.. So where do I go from here.. I barely tightened it maybe 10 foot pounds before it gave out.. all the others are fine please help is there away I can fix this?? I believe the bolt is 5/16 in diameter.
 
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racerone

Supreme Mariner
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Dec 28, 2013
Messages
23,426
Head bolts are 5/16" at 240 INCH LBS and the water jacket cover bolts are 1/4" and are at 60 / 80 INCH LBS
 

Bosunsmate

Admiral
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Apr 7, 2012
Messages
6,124
Always clean threads and bolts prior to use. Detritus in them can seize a bolt up
 

Zack19919853

Seaman
Joined
Aug 17, 2019
Messages
74
I always use oil after using a wire brush to clean the bolts up.. I also try to clean the inside of the bolt hole best I can. I did 240 inch but didn't get past about 120 inch pounds before it loosened up on me.. so ill use a heli coil on them as flyingscott suggest! thank you for yalls answers I'm scared guys lol :nevreness:
 

Zack19919853

Seaman
Joined
Aug 17, 2019
Messages
74
Also when I take the head off yall think the head gasket will still be good or will I need to get another set?
 

jimmbo

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May 24, 2004
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My dad used to reuse the head gasket, even though he had bought a new one. He lucked out and it sealed, but YMMV
 

Faztbullet

Supreme Mariner
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Mar 2, 2008
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13,573
@$) in lbs is 20ft lbs but needs to be done in three steps and no I would not use gaskets as fire ring have been compressed
 

flyingscott

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Apr 8, 2014
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6,371
You have to tighten the head gasket in 3 steps you can't just tighten the bolts up to max torque . It must be done in 3 steps, If you use in/lbs it is 80/80/80 if foot/lbs it is 7/7/7. Depends on your torque wrench if you have a beam one use in/lb if you have something like a snap on you can use ft/lb.
 

Alex Novo

Cadet
Joined
Sep 22, 2019
Messages
25
Sack you did it man and aint that bad yet. Check size, measure right, buy a tap and the right screw, thread,length and thickness. Tap and dont distub the head gasket. Remember my friend ... Aint broken dont fix it.
 

flyingscott

Admiral
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Apr 8, 2014
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6,371
You could do it right or you could do it the way post #12 says. It is your motor and get a tap to clean up the rest of the threads..
 

oldboat1

Fleet Admiral
Joined
Apr 3, 2002
Messages
8,295
must have missed your point. I sounds like a prior helicoil came out with the bolt. If that's the case, helicoil needs to be replaced or just cleaned up with acetone and reattached with another dose of epoxy, assuming no damage.
 

Zack19919853

Seaman
Joined
Aug 17, 2019
Messages
74
Wow never knew it was a three step process wow I see now and I see why.. good to know and I’ll help coil it take the head off and rethread it tap it.. I’ve done a head gasket twice before on cars but never knew there was a few step I usually tighten them a tad bit where the head is flush then tighten them down yo specs!! Thank you all for y’all a help I really do appreciate it!! I’m going to do with a heli cool I almost was think of just re threading the bolt hole and just go with a size bigger if the head bolt hole is large enough! Probably 3:8 would be the next size
 

oldboat1

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Apr 3, 2002
Messages
8,295
been my experience too (complete helicoil pops out with the bolt). Probably need to start fresh.
 
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