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Hello Gentlemen,

Your information has been really helpful. I've placed the putty on the valves and rotated the engine. The putty was compressed to allow for 3/16" clearance so Monday I'll drop the head off to have it evaluated and possibly milled.

My question now is the gasket. It was new, now it has gone through being placed on the head torqued/compressed twice and removed, yet it's never been under engine preassure. Is it okay to use or should I get another?

Thanks in advance.
Andy

Personally I would chance it. It's no big deal to change gasket on the old flathead if you find that you have a leak although I would keep a lookout for any fluid seepage and retorque the head nuts after running the engine.

Old studs and nuts, old cast iron head surface can develop such a rough finish that much of the torque is absorbed by the friction, thus not generating enough clamping force.

I use a thread chaser die on all the studs and a tap through all the nuts. Then, 220-grit aluminum oxide sand paper to lightly polish the bottom of the nuts, use a thin hardened washer and fastener lubricant under the head nuts.

This insures the torque reading turns into clamping force.

jack vines

Troubleshooting 101: Eliminate the obvious first.
Changes: head, washers, different gasket than original, condition of the parts.
Any time a possibility for mismatch, check and recheck the fitment.
Verify the gasket fits the block and the head and has the right dimensions. Recheck the head to block fit. Examine the gasket to see where it compressed or did not.
Also, where it leaked should tell you the path of the fluid, how it got from the water side to the outside or inside. Concentrate on those areas for fitment.
Then go to proper sealing techniques.
Depending on the washer hardness, making it thicker may require more torque if the washer deforms more. Use at least same grade as the nut, grade 5, preferable 8. If you used low grade washers or made from soft metal they may not transmit all the torque properly. What you read on the torque wrench is the force applied, not what the force did or how much actually went into tightening.