Fuel pump or accelorator pump

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Joined
Aug 7, 2010
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Location
McDermitt, NV
My Car
1973 Convertible H Code, 351C 2V FMX
So the reason why I didn't drive it home after the alignment is because when I went to pick it up, the mechanic said they couldn't get 'er started - that they had to push it into the shop and then push it out afterward. He said to "maybe check the accelerator pump."

When I first took her off the jack stands after the 3 week front suspension replacement, I noticed a significant gas leak when I tried to take her for a spin, but I barely got out of the driveway before suspension problems brought an end to the test drive. Back in the driveway after I shut the motor off, I crawled under and saw a virtual "stream" of gas coming from the fuel pump around the inlet/outlet area, but not from the tubing or connections, as far as I could see. It spontaneously tapered to a fast drip, and then eventually quit. I then focused on the bigger suspension fish I had to fry.

When I fired her up again a couple hours later, I crossed my fingers and it worked - no leak. After driving around for a bit, still no drip. The next day I dropped her off at the alignment shop with no problems, she sat overnight, and then she wouldn't start when they went to drive her onto the lift today.

Tonight I went down and poured some gas into the carburetor, and she started right up, then quit after a few seconds even with me pumping the accelerator. So, I'm thinking it's the fuel pump, and I paid a whopping $17.50 retail for an OEM. Tomorrow I'll try to find some time and install it.

Anyone care to give odds on the replacement of the fuel pump solving the problem I described? Anything else I should look out for (ya, I know, fuel filter and such, but I didn't see any symptoms except those I described)?

I feel like "wish me luck" should be in my signature line. :)

Doc

 
Last edited by a moderator:
The accelerator pump wouldn't do anything for start up.

Is this a stock carb or aftermarket?

Streaming fuel isn't good and it stopped by itself isn't good. Check your oil, smell the dip stick if it smell heavily of gas, then the fuel pump needs to be replaced.

For start up lots of things can effect the carb assuming there is no clog in the fuel lines or a leak.

Curb idle could be set wrong, idle air bleeds could be set wrong or the choke if equipped could be set too lean.

First we need to find this fuel leak. Now you could have a torn accelerator pump diaphragm.

Put your hand around the fuel line also and see if you get any wetness, maybe a fuel line rotted out it's possible to.

You could try disabling the coil,no spark, then crank the car to build up fuel pressure in the line, since the mechanical pump will work and then look for the leak.

Have an assistant in the car cranking, let's say 20 seconds at a time, and you look around with a flashlight just be careful if you flood the motor. Relax between cranking.

 
i should also add you could have a stuck float, that would effect starting and could also make it leak and not leak.

when the float gets stuck fuel could be leaking out the fuel vent and then running down the motor, then the float would unstick and magically your fuel leak disappears.

if it suddenly leaks again, bang on the fuel bowl and see if the leak suddenly stops that would indicated the float is getting stuck.

 
Well, you saved my butt again, 72HCode. BTW, everything is stock except for the driver. :)

I finally had time today, after reading your posts this morning, to go down to the shop with some tools and the new fuel pump just in case and removed the fuel line into the fuel filter attached to the carb, then removed the filter and gas came out of both the inlet and outlet side. I blew into it and it seemed clear, and even blew into the carb inlet hole and it, too, seemed to be free of obstruction.

About that time, the owner came up and said I couldn't do any repairs unless it was very minor due to insurance reasons, blah blah blah. I assured him that I would be done in two minutes or tow it in the morning. I dumped some gas in the carb and cranker her over. She fired hard and then died, and would fire up after a few more cranks. I added some more gas to the carb from the can, pumped the pedal 5 times hard, and pressed the pedal to the metal while cranking. She coughed and backfired and then roared, and didn't quit. She's finally safe and sound in the driveway.

I'm not too interested in diagnosing the problem, because I'm going to do the rear suspension and brakes, and then pull the motor and replace the carb, fuel pump, and most of the other stuff that makes it run.

Thanks again for your help!

Doc

 

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