Water & bubbles through head stud nut threads

29Phaeton

29Phaeton

Member
I now see water and air slowing escaping up through the head nut that holds the distributor cable (#8). I'm guessing it's a cracked head, anybody have any other suggestions? This is a GAZ Russian B block with and A head using a B head gasket. I just put the head back and am sure the head nuts were tightened to specification at 55 pounds in the right order. :mad:
 

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This is a common problem when new studs are installed, or if a nut is removed and left off for an extended period of time.
Drain the water and if you can, remove the stud without pulling off the head. You should be able to double-nut this stud because it is taller than the others (except the water neck studs). Tighten the nuts against each other and then use an 11/16" wrench on the BOTTOM nut to unscrew the stud. Once the stud is out, coat the coarse threads that screw into the block with a sealant. Then put the stud back in, using the double nuts to tighten the stud in place. Allow the sealant to set. Then remove the nuts and re-assemble.
Unless the problem truly is a blown head gasket or a crack in the block, this trick usually stops the leaking around this stud.
Marshall
 
I've also had this problem. The fix is soooo easy. Just add a few flakes of radiator sealer - maybe a teaspoon full and drive it. Job done.
The problem arises when water finds its way past the thread at the bottom of the head stud, up through the head and past the nut. A little radiator stop leak will seal the thread easily.;)
 
Another way to fix this is to remove the nut after draining and wrap a goodly amount of dental floss around the stud at the head surface and replace the nut. Sounds goofy but, it works.
 
Torked the nuts in sequence twice, last time after running the car and letting it cool. So if I see bubbles isn't that a sign of compression escaping? I just had my radiator re-cored so I'd rather not use stop-leak if possible. I did re-tap all the threads in the block and installed all new head studs. I used anti-seize on all the stud treads when I installed them.

Doesn't this mean water is making its way across the head gasket from a water jacket? Or does this stud screw all the way into a water jacket? This is the strangest thing I've ever seen after replacing a head.
 
29Phaeton said:
Torked the nuts in sequence twice, last time after running the car and letting it cool. So if I see bubbles isn't that a sign of compression escaping? I just had my radiator re-cored so I'd rather not use stop-leak if possible. I did re-tap all the threads in the block and installed all new head studs. I used anti-seize on all the stud treads when I installed them.

Doesn't this mean water is making its way across the head gasket from a water jacket? Or does this stud screw all the way into a water jacket? This is the strangest thing I've ever seen after replacing a head.
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When you ran a tap through the holes in the block, you will have noticed that they go through into the water jacket. That's where the water comes from.
 
Stop leak won't hurt your new radiator core. I used some when I bought my 28 in 1999, and it stopped the damp spot on the radiator right away.
 
I have found like others have mentioned that after a few miles they seal themselves. I have also used stop leak and even sealed the upper threads with permatex. Stop leak products have been around as long as the cars and they work for most minor leaks. Whether your radiator is new or not they won't harm it.
 
Thanks everyone. I will run it for a while and if it does stop I'll use a bit of stop-leak. So glad to know I don't have to pull the head off again!
 
29Phaeton said:
Thanks everyone. I will run it for a while and if it does stop I'll use a bit of stop-leak. So glad to know I don't have to pull the head off again!
Click to expand...

Did you spray both sides of the head gasket with Copper Coat?

And did you so the initial torque in at least 3 steps? 20, 40, 55 pounds?
 
I always thought that if you use a B block with an A head you should plug the four steam holes and use an A head gasket. If your leak continues I would research this.
 
62pan said:
I always thought that if you use a B block with an A head you should plug the four steam holes and use an A head gasket. If your leak continues I would research this.
Click to expand...

Yes, that's what I had to do for a club member, but only two holes needed to be threaded and plugged.
 
I coated both sides of the head gasket three times each with the copper spray. I did torque the head bolts to 20/40/55 pounds per the Les Andrews manual and I have re-torqued them once after running the car and letting it cool. Posts I found here and on other sites say to use a B gasket with an A head.

Is there any reason not to use teflon tape around the stud threads?


Sent from my iPad using Tapatalk
 
29Phaeton said:
I did re-tap all the threads in the block...
Click to expand...

I'm sure not many will agree but I'm not a big fan of re-tapping threads.

Over the years the original threads become distorted and when you re-tap you remove some of the metal. Then the stud/bolt is 'looser' in the hole.

Better to use a thread chaser or a proper size bolt with slots cut in it to clean the threads without removing metal.
 
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