Exhaust header bolt sealant/ coolant leak

[bandit]

I was getting a coolant leak from what I thought was the head gasket right above my starter so I pulled the heads. I did not see any evidence of leaking around the gasket but what I discovered is the previous owner took out the exhaust manifold studs and replaced them with bolts to install headers.(assuming it was for clearance). What I suspect is my problem is when the studs were taken out, the newly tapped bolt holes opened up access right through to the water jacket in the heads and may be leaking. I can see they applied some kind of sealant to the bolts before but I suspect this is where I am getting my leak from(great to figure this out after the head is removed). Does anyone know a good thread sealant to use on these exhaust header bolts? Is the orange high temp RTV ok to use?

 

[Dako]

At the recommendation of the shop that did my machine work, I used Permatex Ultra Black on mine with very good results. It, or something similar, can be found at most any auto parts stores.

 

[snakeoil24]

The bolts go right into the water jackets. Use brown colored Gasket sealant that stays Plyable not silicone. Also avoid using stainless steel bolts in exhaust bolt holes they leak.

 

[coloradodave]

Just goes to show ya. I have TTI headers and can't run studs. I now use ARP 1" long header bolts with 5/16" heads and ARP thread sealant. For me, this solved the leaking. Tried teflon paste and Permatex 3H sealer first. Still seeped. Thank you Summit.............

 

[vanrj1]

I just worked with a racing shop to breakin my engine and they use a sealer called "right stuff" it's black, they found it to best for quick sealing. I checked at the local auto store and it's like $20 for a tube but that's what I am using now. Sealed fine starting the engine 10 minutes after assembly.

 

[snakeoil24]

Coloradodave you where smart doing what you did. ARP makes the best stuff you can buy period.

 

[67 coronet]

vanrj1 is correct,use "the right stuff".i run a large shop(16 bays)and we have tried every sealant on the market,nothing seals as well as that stuff.

 

[bandit]

Thanks! I just picked up some Right Stuff. Got the heads back on today and will put the intake and headers on tomorrow. I need to put the sealant on the intake manifold bolts too. Anxious to get her fired up again.

Appreciate the help.

 

[wilsonlar1]

Good morning. I'm a new member here and would just like clarification. Is it normal, then, for a header bolt to enter a water jacket? My scenario is I have a '70 Coronet 440 with a 383 and tuned headers. My starter just died and I have to loosen/remove the header on the drivers side to remove the starter. When I removed one of the header bolts, not a stud, coolant shot out the hole. I was very surprised by this as I had no idea the bolt acted as a plug. So this is "normal"?

 

[miller]

Yup.