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Author Topic:   Leaky head bolt. Help!!
Dirt Freak

Total posts: 215
posted November 09, 2002 03:38 PM
. Fresh rebuild on 350 block, new head bolts(not studs), teflon on bolts.... and during the cam break in, I noticed some water seeping from a back, lower head bolt. I shut off motor, retorqued bolt, no change. I then removed bolt, cleaned and reapplied Permatex Thread sealer with teflon. Finished cam break in and thought all was well, but when I shut off motor it was still seeping some water. It was much slower leak now. Whats next??? Is there a better sealant to use?? The head bolts are new, so the threads are good, so I assume the blocks threads must be somewhat poor and allowing the water to seep up and out. It did not leak before the rebuild. Anyone?? thx sixwillwin

Dirt Freak

Total posts: 499
posted November 09, 2002 06:07 PM UIN: 23443678
We have this problem with studs in are motors... the easy way to fix it is with BARS LEAK its the best leak fixer i have found and run it in all my race motors to help seal em up.

Dirt Maniac

Total posts: 199
posted November 09, 2002 09:28 PM
Your problem may be the seat where the head bolt meets the head. If this area is tapered from too many torquings then it should be re cut so it is flat.


Dirt Full Roller

Total posts: 27
posted November 09, 2002 10:12 PM
Sleepy's right. Pull the head and use a drill bit a few sizes bigger than the hole and use it to tapper the hole a little.

Dirt Forum Champ
Total posts: 1565
posted November 10, 2002 09:04 AM UIN: 54865418
one thing you might want to say away from is the teflon tape we found at work when we used treflon tape on hydrolic fittings that pieces of the tape were getting into the system and wearing on the pumps and bearing. it could do the same to a water pump

Dirt Maniac

Total posts: 128
posted November 10, 2002 10:02 AM UIN: 14464409
i would do the drill bit thing and also put just a small amout of sylicone on the bolt threads i have done this with the same problem and that works very well. i woudnt use any type of stop leak in any situation unless its an emergency. i repair radiators for a living, both race car rads and everyday driver rads, i have been doing radiators four 5 years now, and you will be suprised at what stop leak will do to a cooling system. i used to use it all the time until i saw the inside of one of my radiators and wont use it unless there is no other option. also you might change the head bolt. that worked one time also. good luck. charlie norris

Dirt Freak

Total posts: 215
posted November 14, 2002 07:49 AM
I thought I would update the leaky head bolt situation. I removed that head bolt and after cleaning everything up(again), I reinstalled a used head bolt(Manley), which was actually a couple of threads longer than the bolt I took out, and then I coated it with Permatex #2, and presto, no more leaking. This brings something else to my mind, I am just overwhelmed with all the different tubes of this and that at the parts stores, it's hard to tell what to use on different stuff, I used to use Permatex teflon thread sealer before but now I will Permatex #2 on head bolts, so what is the Permatx #1 used for?? I saw that also. I saw it was a hardening type sealer. I use Black RTV in place of intake gaskets, I use Blue RTV in place of Ford 9" gasket, and orange RTV sometimes of other stuff. What are some your other favorites and their uses?? thx sixwillwin

Dirt Full Roller

Total posts: 63
posted November 14, 2002 12:21 PM
#1 is a hardening sealer. we use it sometimes at the shop when we get an aluminum intake that is pitted near the coolant passages. works good for stuff like that


jhon hollomon
Dirt Maniac

Total posts: 181
posted November 14, 2002 12:24 PM
We use the copper rtv on all kinds of leakin' things. It's supposed to seal better with heat. I had a valve cover leak one night after putting blue rtv on.We pulled it off, wiped it off and got it on with about six seconds to spare.Went out and it didn't leak.Sold me on it.

Dirt Freak

Total posts: 247
posted November 15, 2002 01:42 PM
Form-A-Gasket #1
Fast-drying, hard-setting sealent designed for sealing rigid materials and flanges, or patching holes and joints where permanent assembly is desired.
Temp Range: -65* to 400*

Form-A-Gasket #2
Slow-drying, non-hardening sealant designed for sealing cut gaskets and stamped parts. Allows for easy disassembly if required. Use where sealing is more important than adhesion.
Temp Range: -65* to 400*

Blue RTV #6B
O2 sensor safe,makes reliable "formed-in-place" gaskets that resist cracking, shrinking and migrating. Coats pre-cut gaskets to increase reliability.
Temp Range: -65* to 500* intermittent

Orange RTV #27B
O2 sensor safe, same as blue but higher temp.
Temp Range: -75* to 650* intermittent

Red RTV #26B
NOT O2 sensor safe, formulated for hi-temp applications, or heavy-duty use, replaces almost any cut gasket by making reliable "formed-in-place" gaskets that resist cracking, shrinking and migrating caused by thermal cycling, coats pre-cut gaskets to increase reliability.
Temp Range: -75* to 650* intermittent

Ultra Blue RTV #77B
Ultra silicones were developed to meet today's technology changes. O2 sensor safe,low odor,noncorrosive,eight times more flexible than cork/composite gaskets; three times more oil resistant than conventional silicones.
Temp Range: -75* to 500* intermittent

Ultra Black RTV #598B
Same as Blue RTV and meets dealership warranty requirements.
OE specified by: Chrysler,Ford,GM,Jeep,Mitsubishi,Caterpillar,Detroit Diesel.
Temp Range: -75* to 600* intermittent

Ultra Grey RTV #82194
Designed for high torque applications (predominantly Japanese designs) requiring a unique RTV gasket. Other features same as Blue and Black.
OE specified by: Acura,Chrysler,Daewoo,Ford,GM,Honda,Hyundai,Isuzu,Maxion,Mazda,Mitsubishi,Nissan,Subaru,Suzuki,Toyota.
Temp Range: -65* to 650* intermittent

Ultra Copper RTV #101BR
For 4-cylinder, turbocharged or high-performance engines. The most advanced, high temperature RTV silicone available.
OE specified by: Toyota
Temp Range: -75* to 700* intermittent

High Temp Thread Sealant #59235
Locks and seals threaded fittings. Resists leakage, vibration loosening, moisture, hydraulic fluids and diesel fuels. Lubricates threads for easy assembly and disassembly.
Suggested Applications: Head bolts, oil pressure sending units, oil and coolent lines, fuel fittings, brake and power steering fittings.
OE specified by: Chrysler,Ford,GM,Hyundai,Case,Caterpiller,Cummins,Fiat Allis,John Deere,Kenworth,Komotsu/Dresser,Mack,IHC,Volvo/GM.

[This message has been edited by Racer14K (edited November 15, 2002).]

Dirt Freak

Total posts: 215
posted November 15, 2002 04:07 PM
Awesome info, thx Racer14K

Dirt Freak

Total posts: 247
posted November 15, 2002 04:25 PM
Was bored at work, hope this helps.

Dirt Full Roller

Total posts: 61
posted November 15, 2002 09:19 PM
3M Weather strip adhesive to hold the intake gaskets in place. First coat both the head and the gasket and let dry. recoat gasket and apply. Make sure its where you want it because its now glued!

Dirt Full Roller

Total posts: 61
posted November 16, 2002 02:35 AM
I use Aviation Sealer on head bolts . It has
never let me down. Easy to apply with the
brush made onto the cap.

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