MTFCA Forum

Okay, so I'm "fed up to here" with the typical green drops under both my Ts from that cussed, period-correct looking radiator petcock dripping incessantly. The vendors CLAIM the original style (as well as the modern version) don't leak. I say "ha! Prove it!
That said, has anyone bought one or the other in the last year, and indeed do they NOT leak?

Sorry that I can't help you. I did install a #3079 petcock which I purchased from Lang's, but that was five years ago. It has never leaked a drop.

I have never used a modern or reproduction petcock ever! No problems.

Sometimes, even the new petcocks (either style) require some lapping to make them seal.

I use the same petcock thats used in the oil pan. Works great.

I have an original accessory honeycomb so not sure if this would work on a standard.

The stock #3079 petcock is used on both the oil pan and the radiator. So far I have never had a problem with one leaking.

When I had my radiator cleaned and repaired he installed a modern type drain. Seems to work fine unless there is too much sediment collected in the bottom of the water outlet.

I've purchased many of the new copies - both for the c.c. & radiator - so far so good !

Tim - you might just give the "twister" a very slight "luv tap" to seat a persistent dripper !

I stock new ones and have used them on various customer projects over the last 17 years without any known problem.

The only thing I can think of is that new petcocks never fit right in new Brassworks radiators. The lower outlet of a new Brassworks radiator always had to be tapped out some more so they would fit properly. Several years ago I checked threads and the new petcocks were close to correct and the female threads in the radiator required adjustment.

I FOUND OVER THE YEARS THE TAPER WEARS A BIT AND ALLOWS A LEAK, I TOOK MY PETCOCK APART AND RE SEATED IT WITH A DAB OF FINE VALVE COMPOUND, TWISTING THE SHUT OFF BACK AND FORTH WITH SLIGHT PRESSURE, THEN THIN IT A BIT WITH WATER TO FINE FIT IT,, WASHING IT GOOD WHEN FINISHED, WHEN AFTER EACH USE ROTATE THE VALVE WITH SLIGHT IN WARD PRESSURE TO SEAT IT, GOOD LUCK.

Thanks guys, the petcocks I have on both cars are same as the one Steve posted the pic of.
Maybe I'll give it that "quick tap" first, and see what happens. If not, I'll take it apart and try what Richard G suggested.
Otherwise, today we had a pretty nice afternoon tour south of our area. 5 participants. Probably THE LAST one THIS time!!

This thread sounds like fisherman telling their "fish" story.

I have messed with these cars since 1972? I was slightly older than Jonah.

I know how to fix these. I know they are still made the same way. I know how to clean/wire brush/lap/lube them, and just recently learned about the Aviation stuff that works well. I buy new springs and washers and cotters, but i would NEVER claim that I never had one leak. Specially on the sediment bowl, so to you guys that say you never had one leak, I say "wives tales."

"Never" and "always" will never go unpunished. Said a wise mine to me! You nailed it Jeffery!

I've had leaks from sediment bulb shut-off valves, but so far not from a petcock. But I've been at this for only thirteen years.

And sadly, even in my "pre-T years", I've never had one that didn't leak!!
My former '20 Runabout had one of those modern "T handle" valves, the kind that drain through
the hole in the middle of the handle..now IT never leaked! But it was a bit of a pain to use though, given its location.
I'm thinking of getting two of those just the same.

No problem here, but Im using water - other spots in the system seep.
I did have seepage and drips in the fuel line, lapping the valves and using fuel percock lubricant stopped that !

Now it's time to ask, would that compound work with Prestone ?

Rich Bingham wrote: ↑

Sat Nov 21, 2020 10:23 am

Now it's time to ask, would that compound work with Prestone ?

Yes

Tim, I agree with Larry Smith; I use original petcocks in radiator and crankcase both; no leaks ever. I don't think I've ever been to a swap meet where there hasn't been at least a half dozen available. Once I splurged and gave $2 for an extra nice one.

R.V. & Larry...guess maybe I just have bad luck. But I generally don't back down from a challenge...I'll get it licked somehow! At least I got 90% of the oil drips from both cars remedied...they almost don't look like a T anymore on the pavement under the engine! And got the fuel drips stopped too. Yay!