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The head gasked would seal the studs.

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Have any ideas Don?? Water is getting into the pan, but no white exhaust, so doesn't seem that it would be head gasket related. Pressure tests didn't reveal a leak, so I would guess a small internal crack somewhere in the block. Have you heard of issues like this being caused from changing valve guides?

I believe what he is talking about are the head studs they do go into the water. Yes you are to use Permatex No. 2 sealer on all of them then torque them. We used this Sealant a lot at Caterpillar on gasket joints like oil pans and front and rear housings . They say it sets up but does not get rock hard. When I got a few head studs from Max Merritt they said to use it as well. I had thought of this but since it had great compression on all 8 cylinders hot and cold I did not think it could get in a cylinder. Thanks for checking on Facebook.

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And as Don mentioned the gasket should seal around the studs. If there were a leak you would see it at a head nut. I had one that was a little leaky until I had retorqued the head a couple of times. I don't think these would be the source of your issue. Hopefully your pressure test will reveal the problem!

Some of the head studs go directly into the water jacket. When we rebuilt my dad's '38 Super engine we used sealant on all those.

We had to rebuild the engine twice because the first donor block we used (the original cracked) apparently had too much corrosion inside the water jacket that we were not aware of. When the machine shop bored the cylinders it ended up creating a weak spot in the cylinder wall. It was not visible or detectable. Upon first start up we found that one of the cylinders was not firing, and we found water when we took out the spark plug. Apparently the pressure from the piston blew out the weak spot in the wall and water quickly followed. Upon disassembly we found another spot under one of the valve seats that was thin enough to force water through. Bottom line was the block was trash and we had to source a new donor block.

I saw that you bored your cylinders so that's what came to my mind. But with your pressure testing I would think that a leak like we had would have shown up when you tested. Maybe a pinhole leak or crack in the valley under the valve seats? I would think that magnafluxing would show the problem areas.

Sorry I can't be more help.

-Kevin

Don't think anyone mentioned it yet. If you are using acorn nuts, you must be sure that none of them are bottoming out.

Even if it were leaking around a stud, the only place coolant could come out is from under the nut which seems very unlikely. The head gasket seals it around where the stud goes into the block and also these should all be quite tight with rolled threads which I believe (but not entirely sure) began before 1950. Maybe someone ran a tap into all the holes in the block.

My own opinion, of course, but I don't think that the acorn nuts are at all attractive. Good point about them possibly bottoming out, though.

That was my thought as well about it leaking around the head studs it would come out on top of the head around the studs. No to using acorn nuts but a good question. The last thing I had thought of from my first post was all 8 spark plugs looked to clean to clean. They should have been light brown or tan not clean with not much color. My Machine Shop guy said the same thing when I showed him. I'm heading their this morning to talk about what info I have got from everyone here and try to raise the air pressure and look for a leak again. Thanks to all.

You mean your spark plugs were so clean they may have been "steam cleaned?"

Hopefully the higher pressure reveals a problem! It's hard to fix what you can't find!

"And the plot thickens" When back to Daves my machine shop guy and removed the head so we could install the Intake and Exhaust valves with grease on the stems and seats to help hold them in place when we rotated the engine. Changed the water pump to a older one I had so we could steak a freeze plug with RTV on the inlet side . Then we pumped up the air pressure to 50 PSI and found the pump was leaking where gasket goes next to the thin plate clamed it with vise grips to some what hold. Then started looking for leaks again hoping to find something I had removed the studs for the manifold at my shop not thinking about the holes being through so we put 3/8 bolts with RTV on them to seal them up. After turning the engine over and sideways we decided to go upside down while spraying it with soapy water everywhere and no leaks. Installed spark plugs and held the valves up and filled the cylinders with water and keep looking still no leaks ????