The petcock predicament

The past two months have kept me away from the T due to a family emergenc.y,
but now I’m back in the garage trying to figure out what’s next.
The radiator arrived and I’m ready to bolt it on when I realized that it didn’t come with a petcock to drain the radiator, so I set about removing the petcock from the old radiator. It was pretty much frozen so I gave it a good shot of WD-40 and heated it up with a lighter. The petcock still wouldn’t unscrew however the valve began to turn freely, so freely that it came off in my fingers! It did give me a 7/16th hole to unscrew the petcock from the radiator using a screwdriver, without doing damage to the brass with a wrench.
OK, now I’m looking at the petcock sitting here in two pieces.
I can press fit the valve back into the body, but there is no way to make it secure.
This could be a problem with all the rattling going on possible working the valve out and leaking the coolant out on the road .
That wouldn’t be a good, I’m thinking.
I swabbed the parts clean with a Q-tip and it looks like there may have been some thrreads, or maybe not. It could be just scarring on the brass since the markings are so faint.
Suppliers list both original designs ($30) and a new design petcock ($10) so if I can’t get my old petcock to be a good citizen, I can order a replacement and finish installing the new radiator. So this leaves me with some questions:

  1. How do I tell if an old petcock is worn out?
  2. How do I restore an old petcock if it isn’t worn out?
  3. If I order a new petcock, which one is prefered—the original design or the new one?

Thanks for your patience with me.

Sounds to me like your old petcock was missing some parts. Good thing it was frozen up!

The old style petcock works fine here is a link to one from Lang’s:

Thank you, cudaman!
The sooner I order it, the sooner I can get the radiator installed.

Wow those are expensive! Glad I don’t need one.

The thread is a common one. On one T Model we had it was discovered a brass bolt had been substituted. It came out easily and went back in as easily. Another time a Mom-n-Pop hardware store had a petcock of appropriate size and thread for a modest price. Any big box store such as Home Depot or Lowe’s should be able to fix you up as well. Be prepared, they are brass and the cost of brass is up like everything else.

True it doesn’t resemble an original but since we are far from purists that’s what is in there. Before there is a howl, it doesn’t leak. And in the years it’s been in place no one has taken me to task b/c the petcock is not original or original in appearance. The petcock for $29.95 plus s/h plus sales tax can do little more. Your call. :slightly_smiling_face:

Regards, Tom in Taylor Mill KY 41015

While I’m waiting for the new petcock to arrive, I was wondering if I should use Teflon tape when installing it?
Henry certainly didn’t, but would there be any advantage to using it?

If it’s pipe thread, I would lightly wire brush the threads in the radiator, then use either teflon tape or liquid teflon from a tube as a sealer.

Thanks, I’ll do that.