32 4 fuel pressure after running.

[jim1932]

OK we drove the car on the railer, moved it, drove it off an let it idle a couple minutes. Shut it off for 5 minutes, Started it up and moved it to the side of the drive way and turned it off. 2 minutes later gas is dripping fast off the car. Leaking from the diaphragm area. opened the drain valve a hair and it really started leaking. I minute later is stopped.

Is the pump pressurized that much when you stop it?

[DavidG]

If the float valve in the carburetor is seating properly, then yes, there would be residual pressure within the fuel pump and in the fuel line between the fuel pump and carburetor. It should not leak past the diaphragm.

[jim1932]

I went back out and the diaphragm must be shot. My driveway is sloped so the gas tank is higher than the pump. There was almost a quart of gas in the pan I had put under the car. Looks like the tank was slowly emptying itself through the fuel pump. Does not look like the cork gasket is leaking, looks more like the diaphragm has become porous ... or all the screw loosened up... maybe with it getting run for a while for the first time the screws are loose. I will check that in the AM. If that doesn't work I will try the spare pump.

Took the hose off and Blocked it up for now.

[Terry,OH]

Charlie Schwendler sells a diaphragm for the 33-35 pump. If this is what your using I would suggest sending the pump to him for repair. If your using one of the 32 pumps I believe he can make a diaphragm for it. If the pump is leaking from the holes in the bottom the diaphragm is not good, the drain plug will drain the top of the diaphragm where the fuel is supposed to be. Make sure you change your oil since it is possible the fuel has gotten into the engine through the fuel pump adapter stand.

[DavidG]

The fuel pump diaphragm for all original '32-'33 fuel pumps (and the '34 four-cylinder pump) is the same as those for post '33 fuel pumps, the only difference being how the operating stem is attached (detachable for the '32-'33 pumps and staked on the stem on later pumps).

[jim1932]

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I took a closer look. Not sure if this is possible but is seem to be leaking straight through the Pump as if it was porous. I replaced the diaphragm. I wipe it off and the gas shows up half way up the body.

[DavidG]

Jim,

It is possible that the housing could be corroded inside to the extent of creating a pin hole or just a poor die casting to start with that made it this far but no farther.

[G.M.]

Originally Posted by jim1932

I took a closer look. Not sure if this is possible but is seem to be leaking straight through the Pump as if it was porous. I replaced the diaphragm. I wipe it off and the gas shows up half way up the body.

A slight leak on one of the fittings will do this?? G.M.

[Terry,OH]

The cork seal on the upper cap, the gasket on the top for the acorn nut , loose screws around the diaphragm, leaking drain screw, input or output fittings. When it leaks it spreads and it is hard to determine the exact source of the leak. Since the engine ran with this pump I would doubt it is a porous casting. All the above would also prevent the pump from delivering proper fuel pressure.

[Andyr]

FYI..........with the discussion about diaphragms , one should remember that the "new" gas with ethanol eats them up.......one might think about replacing it with a diaphragm made with Neoprene...........

[jim1932]

It has a new cork and the correct neoprene diaphragm.. maybe the drain not seating properly.

[DavidG]

Only if it is leaking at that point. Does your upper casting have a little drain hole on the side of the boss where the drain plug is located? If so (not all have the hole), and fuel is leaking from that hole then your drain plug is the culprit. If your upper casting has no drain hole then your drain plug is the culprit only if fuel is leaking out around the drain plug threads.

[jim1932]

I drove it around the neighborhood for a half our. Not really leaking now.... go figure...