Fuel Pump

[Twins]

Two weeks ago, (after having the car sit for two weeks) when I started it there was a puddle under the a/c compressor/power steering which did not seem greasy and dried quickly with no residue. No further leaks once the car was running. No strong odor and at first I thought it was from the power steering or a/c.

Yesterday, same thing only I noticed that I had to pump the gas pedal multiple times to get the car to start (it sat for two weeks) and the puddle does indeed appear to be gas. Again, the drip stopped even after multiple starts and stops that day. Weather was about 45 out both times.

So far, I don't see any leak from the two lines on the bottom of the pump or up top by the carb. My first inclination is of course that the pump is leaking. Before I go pulling it off I am just curious as to where a leak like this would be (I assume up on top of the pump where I cant clearly see right now, or by the connection to the engine?) and why it would occur at start up (I assume from my pumping the gas repeatedly?) but then not continue?

Any advice is of course always appreciated. Still learning. Car is a 1973 CJ with a/c (although not factory installed - looks like dealer installed many years ago)

Thanks as always gentlemen.

 

[will e]

You should check/smell the oil, sometimes the fuel leaks into the crank case. This is very bad for the oil. I would do this before starting it.

Have you smelled the drip to confirm it is gas?

 

[Don C]

I agree, make sure it's gas. Pump diaphragms can leak into the crankcase or through a vent hole in the pump body. They can also leak around the edge where the two halves join together.

Connections shrink when they get cold and can leak, then stop leaking when they warm up, make sure they're all tight.

Pumping the gas pedal won't make the fuel pump leak. The fuel pump fills the fuel bowls on the carburetor, pumping the gas pedal causes the accelerator pump to draw fuel from the fuel bowl and squirt it into the venturis, from where it's drawn into the intake manifold and the engine.

 

[Twins]

I agree, make sure it's gas. Pump diaphragms can leak into the crankcase or through a vent hole in the pump body. They can also leak around the edge where the two halves join together.

Connections shrink when they get cold and can leak, then stop leaking when they warm up, make sure they're all tight.

Pumping the gas pedal won't make the fuel pump leak. The fuel pump fills the fuel bowls on the carburetor, pumping the gas pedal causes the accelerator pump to draw fuel from the fuel bowl and squirt it into the venturis, from where it's drawn into the intake manifold and the engine.

I do need to take a better whiff of it. It was not as strong a gasoline smell as I would have expected but the only other thing I can think of is that something - even condensation? is coming from the a/c compressor and running down the fuel pump body. I did have the a/c running (accidentally) in the cold about two weeks ago and got a huge amount of water dripping from about the middle of the undercarriage of the car. That was definitely clear clean water.

I'm glad to hear that there is a vent hole or an edge on the pump where the two halves join together or this would really be driving me crazy. It makes sense that it could be leaking from one or both of those spots.

I realized that pumping the pedal could not cause this as there would be no response from the pump itself to that action while the car is not started.

The oil does not seem to smell like gas.

I'll try to recreate it once more and if it turns out to be gas it looks like replacement of the pump is in order. Even if it was the gasket between the motor and the pump for the effort to take out the pump and the cost it is probably worth replacement I think.

Thanks for the advice and anything else you can offer would be appreciated.

Oh, and Happy New Year to all on the forum.