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Sealing Header Bolts

Banzaiii67

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Rebuilt heads, have been magged.. no cracks, and no helicoils..

Fired up, ran it twice. Re-tighten all bolts while warm..Still leaks out of at least 4 bolts :eusa_doh:

I used Permatex #2 and thought i used enough on the threads. Apparently not.

I've heard pipe dope, teflon tape, permatex thread sealer (super 300 i think), ultra black rtv, right stuff, copper rtv, aviation permatex, permatex #2 and the old just throw bars leaks in the radiator.

What works best in your experience ?
 
Had the same problem with my 440. Took the bolts out one at a time and put ultra black rtv on the threads. I'm free of all leaks.
 
ptex

Rebuilt heads, have been magged.. no cracks, and no helicoils..

Fired up, ran it twice. Re-tighten all bolts while warm..Still leaks out of at least 4 bolts :eusa_doh:

I used Permatex #2 and thought i used enough on the threads. Apparently not.

I've heard pipe dope, teflon tape, permatex thread sealer (super 300 i think), ultra black rtv, right stuff, copper rtv, aviation permatex, permatex #2 and the old just throw bars leaks in the radiator.

What works best in your experience ?

I use permatex aviation gasket. Smells like syrup and sticks like hell, so don't use too much. But it is very effective sealing gasoline, oil, water, you name it. I put it on the header stud threads, no (water) leaks. Won't help with exhaust leaks... I would recommend using studs instead of bolts, a good Napa will carry them.
 
If all else fails Indian head gasket shellac.. small bottle with a cotton swab on the cap.... real messy and seals any thing use studs because it doesn't let go after it gets hot and sets up.
 
Mine leaked as soon as I put it together. So I wrapped each bolt with 9 turns of standard white teflon tape, and no leaks for a year! The 2 end bolts I used studs to hold the ex gasket in place while assembling it. Used Ultra Black RTV on those. No leaks. 915 iron heads.
 
I've always used pipe-dope....without any issues.
 
Not trying to highjack the thread here but let me ask a question though of all you guys who are in the know: All these items that you use to seal up them various leaks, do any of them keep the bolts from being rusted in place and possibly breaking upon future removal? I'm asking as I have to put the header back on my rig but I was thinking of using anti-seize...
 
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