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Petcock leaking

Aron Gleason

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So after getting the front of the motor back together I go to fill the radiator and antifreeze is leaking out the petcock. Go to get a new petcock, put thread sealer on it. Get it tight, and its leaking. Threads are good, and the lower tank is fine. What could be the problem?
 
So after getting the front of the motor back together I go to fill the radiator and antifreeze is leaking out the petcock. Go to get a new petcock, put thread sealer on it. Get it tight, and its leaking. Threads are good, and the lower tank is fine. What could be the problem?
Maybe small crack around the petcock area?
 
I don't see a small crack anywhere. Was told it could be a bad petcock
Possible with today’s supply chain of parts. If it does it again with another petcock, I’d say pressure test the radiator and know for sure where’s it’s happening or pull radiator and take it in for shop opinion
 
Assuming it's NPT, you could try swapping it out with a pipe plug and see if the leak remains.
 
Possible with today’s supply chain of parts. If it does it again with another petcock, I’d say pressure test the radiator and know for sure where’s it’s happening or pull radiator and take it in for shop opinion
8115.jpeg
this is the petcock I got.
 
On mine, I put a brass 90, a small ball valve, then a nipple.

No more leaks, and if I need to drain, it doesn't spray all over the k-frame and everything else.

Also, I can put a length of hose on it and drain it directly into anything.
 
So after getting the front of the motor back together I go to fill the radiator and antifreeze is leaking out the petcock. Go to get a new petcock, put thread sealer on it. Get it tight, and its leaking. Threads are good, and the lower tank is fine. What could be the problem?
Contact @themechanic to see how he handled his petcock.
 
If the rad is empty, I suggest pull the petcock and check to see the closed position of the valve. You might be able to see if it is closing tightly.
 
I know sometimes I'll turn it the wrong direction thinking you turn it to the right to tighten it but it's actually the opposite to cut it off. I've had them both ways.
Hmmm. Interesting, I didn't think of that
 
Well wouldn't you know it, I was turning the wingnut the wrong way thinking I was closing it, when I was actually opening it.
 
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