Fuel Pump Not working

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captainbah
Posts: 6
Joined: Sun Dec 03, 2017 12:50 pm

Fuel Pump Not working

Post by captainbah »

Hello to all,

The brass adapter from the fuel pump outlet to the fuel line cracked. I replaced it, hooked the fuel line back up and I don't get any fuel pumping.

I did pull the fuel pump out to replace the adapter...because it was so close to the frame cross rail and I could not get easily put the adapter in.

When I put the pump back in, I tilted the "arm", to make sure it went under the cam.

Any ideas why the pump stopped working?

Thanks

Joe Johnston
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Re: Fuel Pump Not working

Post by Joe Johnston »

Any chance you misconnected the lines? In other words, the line FROM the gas tank, is now connected to the OUT port of the pump, instead of the IN port? Not likely, but possible.

It probably needs more cranking to get the gas sucked into the pump. Try squirting some gas down the carb and getting it to run a few seconds. May need to do this a couple of times to get fuel drawn to the pump.
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T-Bird Bob
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Re: Fuel Pump Not working

Post by T-Bird Bob »

Hi,
What Joe said!
when you open the pump it looses it's prime. It needs to run for 30seconds at 1500rpm or so to start pumping again.

Have fun!

Bob

captainbah
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Joined: Sun Dec 03, 2017 12:50 pm

Re: Fuel Pump Not working

Post by captainbah »

Joe, Bob,

Thanks for the recommendation to put some gas in the carb and run it. I saw this on another forum (sorry..I strayed) and then a reply that said that was a waste of time...but it's obviously potentially an "easy fix", so I'll try it.

Joes...thanks for the suggestion about checking the lines. One is a rubber line and the other is a stainless line...so the attachments are completely different....even I could not mess that up. : )

Thanks for your help,
bruce

bobgreco2000
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Re: Fuel Pump Not working

Post by bobgreco2000 »

I am just getting ready to start our 55 after rebuilding the engine and found this thread helpful.

Would it help to fill the fuel pump first? I'm thinking of filling it though the rubber inlet hose.

Thanks much!!

Bob

ICON 1956
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Re: Fuel Pump Not working

Post by ICON 1956 »

Is there fuel in the glass bowl ?
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paul2748
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Re: Fuel Pump Not working

Post by paul2748 »

Never heard of having to prime an auto fuel pump. Pour some gas down the carb to start the engine. The pump should pull the fuel up as the engine is running, assuming that the lines are ok. One problem may be a bad soft line, either sucking air or had an internal clog.. If that doesn't do it, the pump may be faulty. Have you checked all the fittings. If you have an air leak in any spot the pump will not draw.
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T-Bird Bob
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Re: Fuel Pump Not working

Post by T-Bird Bob »

Hello Paul,
In know, but this is a Thunderbird specialty!
The fuel line goes up with the frame rail and then down to the pump. If you introduce air in there and have low fuel in the tank, this is more air than the diaphragm of the pump can displace at low speeds (i.e. starter rpm).
So you need the fuel bowl primed and have the engine run at high idles for some seconds. The high RPM with the inertia of fuel will make it possible to overcome the air bubble an prime the pump.

Have fun!

Bob

captainbah
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Re: Fuel Pump Not working

Post by captainbah »

Hello All,

There is fuel in the fuel filter glass.

I put a new pump in the engine and it still won't pump fuel...so this is leading me to believe it's not a pump diaphragm issue. I am still not convinced I am installing it correctly, ie, putting the actuator arm under the lobe/cam that drives it. I took a picture of inside the engine block and I can see the lobe and it's pretty high..so it seems like I am getting the arm underneath.

The tank is 1/4, so I am considering filling to at least 1/2 fuel to see if this will help the head pressure.

I have a small hand pump that can be used to pull brake fluid out of the reservoir (as an example). I am going to hook it up to the fuel line just before it gets to the filter to see if I can pull fuel to that point, so at least I know the pump and all lines are primed (although I'm not sure this will also pull out all the air).

Also going to inspect the fuel filter on the off chance that some how it got clogged.

thanks,
bruce

dustinp
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Joined: Tue Jun 23, 2020 9:32 pm

Re: Fuel Pump Not working

Post by dustinp »

New to the forum, and just saw your post, and was wondering how your progress has been on your fuel issue.

I had a similar situation last fall on my '56 T-bird 312. Wasn't getting fuel pumped up into the fuel bowl. I replaced the pump with an Airtex replacement OEM style pump, but the problem persisted. I was getting some fuel into the bowl, but just barely enough for the engine to idle. Any increase in throttle would cause it to die. I checked each line between the carb. and the tank, and none were obstructed. I finally did a pressure check on the new pump, and found it was only putting out about 0.5 psi instead of 4-5 psi, so a faulty new pump. A second new pump solved the issue.
Hope you have yours going, but thought that may be one more thing to check in case you are still working on it.
Good luck!

captainbah
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Joined: Sun Dec 03, 2017 12:50 pm

Re: Fuel Pump Not working

Post by captainbah »

DustinP,

Thanks for the info. The new pump being defective crossed my mind. There is a local "old" ford mechanic that I work with periodically. He recommended pressuring up the fuel tank. He said getting fuel to the pump is a known issue. I have yet to try that...maybe this long 4th of July weekend.

I am not getting any fuel out of the pump. How did you check the pump pressure to determine it was low?

Thanks
bruce

captainbah
Posts: 6
Joined: Sun Dec 03, 2017 12:50 pm

Re: Fuel Pump Not working

Post by captainbah »

Final Update: The fuel pump is working and the car is running well. Kind of embarrassed to report what happen. I had the lines backward. The old fuel pump inlet was in the same position as the new fuel pump outlet. Ended up taking it to a former ford mechanic, who spent about 4 hours figuring it out. The old pump and new pump pretty much looked identical, except for the location of the inlet and outlet. Looking from the top, the old pump inlet was at about 5 o'clock and the outlet was at 6 o'clock. The new pump inlet is at 9 o'clock and the outlet is out 5 o'clock. Of course, after it was fixed, I found plenty of pictures of the new fuel pump in the engine bay, which if I had looked for these first...would have solved my problem.

The good news is neither the inlet or outlet rest on the frame/cross member, like the old pump, so the fitting won't snap off again when I go over a bump. Thanks to everyone that sent information to help.

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