Gas shut-off leaks-I think
 

My shutoff valve looks like all the ones in the catalogs, so I assume it is a late model replacement for the original. I shut it off faithfully after each trip (in and out of the garage) but the carb is still covered with gas, and it drips on the floor. I am inclined to get a hardware store ball valve with brass fittings to the flared gas line. Les Andrews says the valve is 1/2" NPT, but mine measures about 0.550" male thread OD, or closer to 3/8" NPT. Do I have an oddball or is Les wrong? I prefer to have the correct replacement in hand before removing the leaker.

Re: Gas shut-off leaks-I think
 

Russell to be sure it is the shutoff that leaks disconnect the gas line at the carburetor and put a can under it and test it.

Re: Gas shut-off leaks-I think
 

Appreciate the tip. I flunked Gas Line 101 in college.

Re: Gas shut-off leaks-I think
 

The use of EZ Turn Lubricant will stop the petcock from leaking for a while and make it much easier to turn. See https://www.aircraftspruce.com/catal...ezturnlube.php

If you drive your car a lot and turn off the gas each time the lubricant will last about 6 months. Drain the tank then take the valve apart and smear it with the lubricant and re assemble it.

Re: Gas shut-off leaks-I think
 

Try tightening the nut a bit behind the on off handle! Test as stated above first. or remove carb and check that all jets etc are tight along with the float adjustment.

Re: Gas shut-off leaks-I think
 

I have replaced my shutoff valve twice over the last few years due to internal leakage when closed. $25 in fittings and a ball valve from Ace hardware installed on an extra fuel line equals no more shutoff valve issues. I did buy a flair kit from HF for $10...


I leave the tank fuel valve open and use the ball valve as the main shutoff. I also run the carb "dry" when parked inside the garage.

Re: Gas shut-off leaks-I think
 

Great photo. Per Joop's suggestion I discovered that the valve does, in fact, leak. I think I will use your suggestion, and I already have a flaring tool.

Re: Gas shut-off leaks-I think
 

Good luck measure twice then one more time before you cut the line because it has to fit spot on as there is no way to manipulate the distance. I cut the line on the curved side (where I wanted the valve located) and then measured the distance to the factory valve (straight line = easy measuring) but also visually checked the distance before cutting the second time (the ball valve displaced pipe) I installed the valve to rotate towards the direction of flow when on.



Works good and you can only see the valve if you look under the dash.

Re: Gas shut-off leaks-I think
 

I did similar, I got tired of replacng the leak proof valves the vendors sell.

https://www.fordbarn.com/forum/attac...6&d=1697144476

Re: Gas shut-off leaks-I think
 

Valve thread size is 3/8" NPT.

Re: Gas shut-off leaks-I think
 

If you mean the part of the valve that screws into the tank? Les is
wrong. Not 1/2" npt. It's either 3/8" or 1/4"