'66 SMALL BLOCK HEAD GASGET LEAK

[Rob A.]

I worked on a '66 small block engine this weekend. The heads were installed with the usual quality felpro gasgets and torqued in the proper sequence. There is a small coolant leak from the outer edge of one of the heads at the gasget, where the head meets the block. Would retorqueing the head bolts help at this point, or does the gasget only compress once? Can any type of sealant be applied externally if the leak is small enough?

[Wayne P.]

Re: '66 SMALL BLOCK HEAD GASGET LEAK

Head is probably warped, but before removing to be checked, retorque.

[Rob A.]

Re: '66 SMALL BLOCK HEAD GASGET LEAK

Wayne,

The shop that did the valve work also milled the heads, insisting that a blown head gasget might occur if they didn't. Hopefully, retorqueing will stop the leak.

[Clem Z.]

Re: '66 SMALL BLOCK HEAD GASGET LEAK

did you use sealer on the head bolt threads?

[Rob A.]

Re: '66 SMALL BLOCK HEAD GASGET LEAK

Yes, I did use sealer on all the bolts. I'll take the exhaust manifold off today and take a closer look, but it appears to be coming from where the head meets the block, only on the outside.

[Rob A.]

Re: '66 SMALL BLOCK HEAD GASGET LEAK

I have the car up on jacks quite high and removed the exhaust manifold. upon closer inspection it looks like one of the freeze plugs is leaking. Fortunately, the mating surface between the head and block only looked wet. I was thinking of trying to re-seal it from the outside, since the leak is so slow. How much coolant will come out of the block drain if I decide to remove the freeze plug and replace it?

[Rob A.]

Re: '66 SMALL BLOCK HEAD GASGET LEAK

I replaced the leaking freeze plug, glad it wasn't the head, or head gasget,
Thanks....