Fuel Pump Failure

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marlinh
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Fuel Pump Failure

Post by marlinh »

A little over a week ago my car seemingly ran out of gas. Fuel gauge has been inaccurate but only had a few hundred km after topping up because I reset the trip meter every time. Fuel line and filter was empty of gas so I hitched a ride to a gas station filled a jerry can and got the car going. Fast forward three days ago, the car died again. A kind Samaritan towed me to a gas station and I topped up the tank but it still wouldn't start. Tank was definitely not empty. Fuel line and filter was. I sucked fuel up to the pump and it still wouldn't start. So, I replaced the pump and the car ran fine.

Here is my question. When a mechanical fuel pump fails is it typical for the fuel lines before it to be empty? Has anyone ever had a fuel pump fail and then work again?

The pump that was on the car was aftermarket and brand new. No more than 4 months on the car that was barely driven due to Covid. And yes, Petros I know they are 'junk out of the box'. The tank that was in the car was a used one that had a dent in the bottom of it. I removed the tank hoping to find damage to the pick up tube but it was fine. I pressure tested the fuel line from the pump to the tank and no pinhole leaks. I am sure that I had at least a third of a tank of fuel in the car when it first died on me and it was almost full the second time. Could it have been the pump both times? Curious for feed back from any one else who has seen this before.

Thanks for all your help.
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slimdude85
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Re: Fuel Pump Failure

Post by slimdude85 »

Have you tried running a hose from the fuel pump inlet, eliminating the fuel system from the pulp back, into a bottle or can with gas in it to verify the pump is bad?
Do not be afraid of sudden fear nor of the onslaught of the wicked when it comes; For the LORD will be your confidence and will keep your foot from being caught.
‭‭Proverbs‬ ‭3:25-26

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slimdude85
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Re: Fuel Pump Failure

Post by slimdude85 »

As far as line being empty, it stands to reason that would occur. Between gravity, siphon action, and lack of suction keeping the fuel from moving to the rear as you accelerate, there’s nothing to keep it in the lines if the diaphragm in the fuel pump has failed, as is likely the case.
Do not be afraid of sudden fear nor of the onslaught of the wicked when it comes; For the LORD will be your confidence and will keep your foot from being caught.
‭‭Proverbs‬ ‭3:25-26

I have learned to kiss the wave that slams me into the Rock of Ages. -C.H. Spurgeon
xirdneh
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Re: Fuel Pump Failure

Post by xirdneh »

Did you replace fuel filter or check to see if its loaded up? I have had fuel filter that stopped the engine. After sitting for a bit the engine would run again. Sometimes for hours.
Love those Tercell 4x4 wagons but they sure suffer from road noise.
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marlinh
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Re: Fuel Pump Failure

Post by marlinh »

Fuel filter is also new with no restrictions. Yes, I am familiar with that issue xirdneh. I've seen it before.

Slimdude: I didn't try that at the time being in a gas station parking lot. Just wanted to get home. It fired right up after replacing the pump so that was enough verification for me that it was bad. My curiosity is the empty lines checked very shortly after the car stalled. Fuel draining back makes some sense, but NO gas in the filter, not even in the bottom of the bowl? I would expect the supply line to be dry just before the pump.
Angel
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Re: Fuel Pump Failure

Post by Angel »

I’m having a similar issue and not having any luck figuring it out. I replaced the fuel pump but the car still drives a few places and at some point after turning it off for a half hour or so it will start, die, then refuse to start again without being primed with gas or starting fluid.
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marlinh
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Re: Fuel Pump Failure

Post by marlinh »

Hi Angel, did you replace the pump with a new one? It may be defective and be losing it's prime. Or you have a pinhole leak in a hose or pipe from the pump to the tank. Check carefully. Where are you located?
oldfaithful
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Re: Fuel Pump Failure

Post by oldfaithful »

I replaced my fuel pump with a new one in February and it started doing the same thing, I bought another one and it worked fine, just because they are new, they can still be defective.
brucnich
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Re: Fuel Pump Failure

Post by brucnich »

Did the new fuel pump keep it from dying all the sudden, think mines having the same issue, but fuel also contaminated my oil. It wont turn over anymore tho and the previous owner bypassed the fuel filter which I think caused a clog somewhere. But back to being on topic, did you ever figure it out, please tell me I dont have to re-rebuild my carb.
I dont know what I am doing but I can make vague assumptions let you fill in the gaps for me and let you think I knew it all along...
xirdneh
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Re: Fuel Pump Failure

Post by xirdneh »

Something came to mind about this. Could it be something blocking the air that needs to enter tank to replace space taken up by gas as it is being drawn out. Simple test after car dies would be to quickly remove gas cap and listen for air being sucked into tank.
Love those Tercell 4x4 wagons but they sure suffer from road noise.
brucnich
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Re: Fuel Pump Failure

Post by brucnich »

Oh shoot yeah I got another recommendation for nwno regarding air flow as well. There is a hiss opening the gas tank tho so I'll look into it! Thanks!
I dont know what I am doing but I can make vague assumptions let you fill in the gaps for me and let you think I knew it all along...
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Petros
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Re: Fuel Pump Failure

Post by Petros »

brucnich wrote: Sat Feb 20, 2021 11:26 pm , but fuel also contaminated my oil. It wont turn over anymore tho and the previous owner bypassed the fuel filter which I think caused a clog somewhere.
if you got fuel in your motor oil, the only way this can happen is if you have a leaky fuel pump diaphragm and it leaks into the head, and drains to the oil sump. also, if running really rich, it can wash down the cylinder walls and eventually make it to the engine oil. check for rich running (black soot on the spark plugs and piston tops), and see if your fuel pump is leaking fuel externally out the weep hole on the bottom of the pump.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
brucnich
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Re: Fuel Pump Failure

Post by brucnich »

I'll check it out thanks, feel like if someone's asked a question on this forum you probably know the answer from what it seems, so thanks
I dont know what I am doing but I can make vague assumptions let you fill in the gaps for me and let you think I knew it all along...
SoCal
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Re: Fuel Pump Failure

Post by SoCal »

I also am having fuel pump issues. 3 times now in the past 4 weeks the car has conked out while driving. 3 times Ive had to tow it home and its frustrating. Luckily I installed a custom folding tow bar mounted on the front bumper, I just have to go get the truck and tow it.
The problem is fuel delivery. I rebuilt the motor and overhauled the carb and it runs really good when running. When it would quit, I could smell no gas in the carb top and no gas in the sight glass. I took off the supply hose from pump to carb, the 6 inch black one and filled the carb and it started right up. I took a clear hose and hioked it up to the pump to carb spout and turned the motor over. No gas at all was being pumped! I took off the head cover and looked at the pump arm and it was 1/4 in away from the cam eccentric knob. I took the fuel pump out and bent the arm with few whacks of a hammer and bent it straighter a bit. Reinstalled it and it worked! The car started up and idled smoothly and I took it out and its all fixed! But thats what I thought, I drove it not 5 miles and it conked out again and now Im really scratching my head. All new rubber hoses were installed including the tank hoses. Im stumped :(
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Petros
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Re: Fuel Pump Failure

Post by Petros »

you can try a different pump. sounds like that is the problem. many of the Chinese fuel pumps are junk. I had the original fuel pump on my car that was over 30 years old, it eventually failed and I had no spare so I bought one from the local autoparts store. supposedly OEM, made in china, it worked for a while, after only a year I was smelling gasoline, it was leaking out from around the metal dome edges, that cover is swagged onto the the housing. I took it out and took a punch tool and worked it around the outter edges tightening its grip around the edge, solved the leaking. but I dont trust it and I bought a japans made fuel pump on-line, and switch it out after it arrived. I kept the repaired Chinese pump as a spare.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
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