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I'm working on a complete restoration. I rebuilt my engine two years ago. Finally got it in the frame. It runs great but anti freeze comes out of 4 nuts on the head. There is no anti freeze in my oil. What is causing this?

Most likely the studs concerned penetrate the water jacket and have not been sealed sufficiently when installed. Or, the other likely explanation is, you have a blown head gasket. Either way, to fix it, you need to remove the head.

I did'nt know that the studs had to be sealed. This was my first engine rebuilt. So all of the studs need to come out and sealed. What do you recommend that I seal them with?

If you have the correct studs, although the two ends may appear to have nominally the same thread, the end that goes into the block has an interference fit to facilitate sealing so it's minutely larger in diameter than the other end. Perhaps you threaded the wrong end into the block?

I'd use old-fashioned Permatex #4 as a sealant (the brown, thick & gooey stuff).

On the other side, if it's a blown head gasket, see this thread. Seeing you said earlier"....It runs great but anti freeze comes out of 4 nuts on the head....", if the leaking studs/nuts are in a similar location likely the head gasket. If they are in diverse locations likely non sealing studs.

The leaking studs/nuts are in diverse locations so it is likely it's the non sealing studs. Either way I'll have to replace the head gasket when I take the head off unless you know of a way to save it.

G'day all, I would suggest that you do not have to remove the head. I would drain the coolant (after marking the leaking studs of course). I would then in turn remove and replace each offending stud from the block using two thinner than normal 7/16 UNF nuts locked onto the stud. I would then use the permatex No 4 suggested by O D on the block end of the stud and re-insert the stud to the block with the two nuts on the stud. I would then unlock the two nuts and move onto the next offending stud. If you are not sure about the process, consult a mechanic on the matter. That is what I would do anyway. Good Luck Peter Toet

Might work, give it a try. My own experience is that the jam nut method doesn't hold the stud sufficiently tight to fully tighten the interference thread into the block. Stud installing/removing tools I'm familiar with use a knurled wheel to jam and hold the stud and as that would ruin the thread, you've got to grasp it in the center section between the threaded ends, thus meaning the head must be off.

If you need a picture of a stud remover/installer let me know.

On You tube there is a short clip.

Seeyoutube.com/watch?v=WGXjTK0JP3g

Reading all of this about cylinder head studs, I had a thought: How much do the studs need to be tightened in the block? It would seem to me that if they have a good and proper threads, the threads in the block are good, and the threads have been sealed with the appropriate sealer - they do not need to be very tight - certainly not as tight as the head nuts. The force on the studs when the cylinder head is torqued would be a pulling force. Any thoughts on this?

(o[]o)