401 head gasket trouble--HELP!

[chrisnsarah]

Coolant is leaking from the rear lower corner of the head gasket. I checked the head torque-it's fine. Heads and block were both milled slightly and magnafluxed. To add insult, it's the rear lower corner of both heads. The right side is the worst, it's a drip every 5 seconds when the system is under pressure. We used the Felpro-blue no retorque gasket and installed it dry (no coppercoat). What did I do wrong? It looks like I'll be pulling both heads off. Should I spray the gaskets with coppercoat or put some kind of sealer like tack sealer around the cooling ports?

[Cecil14]

I don't believe you are suppose to use any kind of sealant on head gaskets. You did them right going dry. Did you torque the bolts in the right pattern? If not you may have warped them...

Are you sure it's the heads and not the intake? If the intake was leaking it could be running down both heads and make it appear that the heads were leaking when really they aren't....

Anthony

[chrisnsarah]

We followed the tightening sequence and torqued in stages- up to 110ft-lbs.
I wish it was the intake leaking-much less involved, but it's definitely the heads. Both exhaust manifolds and the heater core are off and I used a cooling system tester to pressurize the system, so it's easy to see where coolant is coming from.

[chrisnsarah]

Here's the latest update, andno it's getting strange. the coolant is actually coming out from under the boltheads, not the gasket. I got hold of the machine shop that did the block and he said some head bolts on AMC motors may be exposed to a cooling passage and they need to be coated with sealer, He said it's mentioned in the manual that certain bolts need to be sealed. Is this true? I hope it is, and how would you seal them?

[Cecil14]

I'm not sure on the V8s but I know on my six there was one bolt that we had to put RTV on and it got torqued just slightly less than the others. Someone will chime in with the right answer here shortly.

Anthony

[gsmikie]

rtv is what i used on open head bolts ford and gm both have a sealer they sell at the parts counter for head bolts ford uses a relese angent to get them out

[illegalFSJ]

If you look at a picture of the head in a Haynes Manual, you'll see the bolts numbered. The #7 bolt on the driver's side needs to have a non-hardening sealant smeared on the threads during installation.

[badaboom]

Coppercoat the head bolts threads seen it done many a time. This may resolve your issue