stud nuts leaking coolant?

[snacob14]

just got my motor together and the head studs are leaking coolant. its a sleaved big bore and we had to turn down the shoulders on the studs to fit around the sleeve. can this be cured with an acorn nut and a copper washer?

[machwon]

acorn nuts and copper washers will help. you may need to use some sealant on the washer and a regular flange nut or an acorn nut. let it sit overnight and it should seal it.

[k7mm]

Use some of this to seal your head.I've been searching for 4 years to find this stuff,never knew what it was until recently.This is what Curtis Sparks used to seal the head on my Harold Goodmans' Pro 265 cylinder.It's close to $20.00 a tube.
Keith

[snacob14]

thats what my builder uses. His grandson put the head on and use a regular nut and washer. I'm thinkign the acorn and copper witha little sealant will do the trick

[wilkin250r]

Had the same problem, leaking from the nuts themselves, not from the washers.

I cured mine with Loctite thread sealant on the threads, and of course new copper washers when I rebuilt it.

[Travwyatt86r]

Originally posted by snacob14
just got my motor together and the head studs are leaking coolant. its a sleaved big bore and we had to turn down the shoulders on the studs to fit around the sleeve. can this be cured with an acorn nut and a copper washer?

Try acorn nuts before gooping up your head with that stuff. Acorn nuts alone solved that exact same problem for me when I was using regular nuts.

[Jonny B]

Just a thought, but do your head studs hold proper torque. I had a cylinder that would leak at the studs, I couldnt get the proper torque spec because of weak aluminum theads in the cylinder.

[machwon]

There are instances with stock heads that have been milled and rechambered where the acorn nuts are not deep enough. You may need to use a couple washers, extra thick washers or use the goop as mentioned. If you do goop it, just wipe the excess of immediately after you put it together and no one will know.

[wilkin250r]

I tried acorn nuts on mine, but because the head was an o-ring head and I had no gasket, the head bolts were too tall, and I couldn't get the acorn nut down all the way.

Some acorn nuts are actually just a regular nut with a small metal cap welded on the top. Mine actually punched through the cap.

[JohnBeton]

Best is to run the engine for a couple of minutes, let it cool down and retorque. Most of the times it already stops leaking from the studs.

[Pumashine]

Originally posted by wilkin250r
I tried acorn nuts on mine, but because the head was an o-ring head and I had no gasket, the head bolts were too tall, and I couldn't get the acorn nut down all the way.


Good observation. Always see if the nuts will touch the head before torquing them down. As long as its touches, then add the copper washer and you are good to go.

Will be mail a set of copper washers on Monday snacob14

[DnB_racing]

Originally posted by machwon
There are instances with stock heads that have been milled and rechambered where the acorn nuts are not deep enough. You may need to use a couple washers, extra thick washers or use the goop as mentioned. If you do goop it, just wipe the excess of immediately after you put it together and no one will know. whats wrong with three bond?
its quality sealant, and only takes a tiny, tiny amount.. its better then a leak!!

[snacob14]

well, my leaking bolts turned into a full blow water leak. Luckily shut it down before anything bad happened I hope. fouled a plug with antifreeze.

[jcs003]

whats the gasket look like? does it have a blown out section?