#7 head stud leaking water

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KEN2939

Junior Member
Put a new head gasket on due to a distributor problem. After running awhile the engine developed a water leak at the stud nut when cold. Retorque the head per the manual. Used a Best composite head gasket. Can I remove the nut and apply RTV and retorque. Head studs were not replaced and had no issues prior. Engine does run good
 
I would try removing the stud and use RTV on it. Originally the stud holes did not go into water, but 90 years later who knows what happened.
 
With the head off last time, what size pistons does it have? The bigger the bore, the lesser the distance from stud to bore. If it has a noticeable gap between stud and the boss bore ID then a dam of sealant or maybe some waxed dental floss might work. Even removing the nut can sometimes make things worse but at this point, it's worth a try.
 
It is a good idea to drain coolant BEFORE loosening ANY head nuts.

If not drained then coolant can end up in oil pan.

Coolant in oil can damage bearings.
 
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Something of a common problem. When I had a leaker I went with the advice of putting aluminized stop leak in the cooling system which stopped the leak pretty quick. Five years later still no problem.
 
I have seen blocks where some ham fisted brute at some time had screwed the head studs in too far and broken out the cast iron Henry left there to prevent your problem. My solution was similar to Mulletwagon's above and with the same results. That was about 40,000 miles ago and it's still fine. If I ever have to redo that engine, I'll sea; the thread when I screw the probably new stud back into the block. Until then, I say if it's not broken....
 
I appreciate all the answers and feedback. I drained the radiator down and the leak stopped going to try RTV and possibly aluminized stop leak. I have 3 A’s and still learning. Again thanks for all the help. Love the Ford Barn
 
These slides may help you. Studs should be hand tight. Tightening the studs with a wrench causes the stud to bottom and breakout the bottom of the hole in the block.
 

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I did read not to over tighten the head studs if replaced. The head bolts were in good shape and many suggested not to replace them.
 
This problem is usually caused by uninformed but well meaning people over the years not knowing that the holes are "blind". Expecting a leak, they put sealant on the threads and screw them in. The next fellow removes the studs, leaving behind a little sealant. This happens a few times and the bottom of the hole is filled with old sealant and the studs cannot be screwed all of the way in so they are forced in. That breaks out the cast iron at the bottom of the hole and creates the very leak the earlier guys were trying to prevent. That's my version of how this thing happens but I'm always ready to hear another
 
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Synchro909 said:
Tghis problem is usually caused by uninformed but well meaning people over the years not knowing that the holes are "blind". Expecting a leak, they put sealant on the threads and screw them in. The next fellow removes the studs, leaving behind a little sealant. This happens a few times and the bottom of the hole is filled with old sealant and the studs cannot be screwed all of the way in so they are forced in. That breaks out the cast iron at the bottom of the hole and creates the very leak the earlier guys were trying to prevent. That's my version of how this thing happens but I'm always ready to hear another
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I gently chase the holes in the block using thread chasing taps, not regular taps. I then check to be sure the holes are thoroughly cleaned (taps, picks, carb cleaner and compressed air on a small nozzle blowing from the bottom of the hole all play a part). Tedious, but worth doing right. Blind holes get copper antisieze only on the studs. I run them in by hand, then just a light bump with pliers to be sure they have seated. Holes that have already been punched out get Permatex #2 on the threads.

I prefer Permatex #2 over RTV for threads. Much easier to clean later. RTV is fine for gasket surfaces where you have a flat surface to scrape.
 
Sounds like the right way is to remove the head and stud. Install a new stud with sealant in the block. Think I might try the suggested aluminum stop leak. Nothing to loose. Does the coolant make its way into the cylinder. I only have water in the system right now.
 
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