1936 radiator petcock

[Blastfromthepast]

My radiator petcock has a slow drip.
Has anybody taken one apart to fix the problem.
Is there a packing inside them. My valve moves to easy.
It doesn’t feel like it’s a tight fit. Thanks, Blast

[DavidG]

If it is an original one, there's no packing inside, just a tapered fit between the shank of the handle and the base. If it is leaking and turns too easily, the tension spring on the shank opposite the handle is likely broken and needs replacement. A thorough cleaning of the base and the shank plus a new tension spring should stop the leak unless there is corrosion damage in the base or on the shank.

[VeryTangled]

I'd advise caution if you are contemplating removing the petcock for inspection or service. They are brass and a gentle approach would be wise to prevent frustrating complications.

[alanwoodieman]

I would suggest trying to remove the movable part WITH OUT removing the pet cock from the radiator, it will most likely not come off with out a fight and you could break it loose from the tank. I have used fine grit valve grinding materiel to clean the taper and then as said put on a new rear/tension spring

[VeryTangled]

Another note that I found out on my '35 and '36 which each had 1937 engine blocks. The cars have correct year radiators, with drains. But the later block also had drains.

Personally if I want the coolant out I'd probably go for removing a lower hose.

Plan ahead for A LOT of fluid, like 5 gal., when you do get things flowing. One normal modern radiator drain pan will not get you through the whole job.

[Blastfromthepast]

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Thanks guys for input. Unfortunately like alanwoodieman said be carful you could break it off at the tank. Guess what, I broke it off the tank. Tried to unscrew it and just kept turning. Broke free from the tank. Any suggestions to fix it. I already tried soldiering but no good.
Maybe epoxy or to the radiator shop.

[feufeu]

I had the same issueon my 37 radiator. wanted to replace the petcok and i broke it.
So i drilled a hole of 18mm in the radiator, and put in the hole a brass part I made. The internal of the part was threaded 1/4" NPT (like petcok). this part was soldered by radiator shop (didn't want to solder it myself...)

[Blastfromthepast]

feufeu, thank you for the pictures. The brass adapter you made looks great.
I don’t know if anyone makes a brass fitting like the one you made but if the
don't you should make a few and offer them on the forum. Even a little epoxy
or sealer around it and press it in. I’ll bet it will work. Blast.

[marko39]

I imagine you could solder in a 1/4 npt brass coupling which if you wanted turned down just enough to leave a small flange.

[Blastfromthepast]

I’m terrible at soldering. I tried all day soldering that radiator.
I usually never surrender but today I did. Took it to a radiator repair shop.
I hope to have it back soon. Thanks guys for all your responses. Blast.

[feufeu]

Yes it's very difficult to solder a radiator because the two boxes (top & bottom) are tin soldered, so if you heat too much the result will be leaks.
feufeu.

[G.M.]

Look on Usbrassandcopper.com They have petcock valves
that look just like the original ones. G.M.

[KiWinUS]

Delete. Sorry