How would you store a mildly used electric fuel pump?

you said "...no gasoline to act as a heat sink, and the pump motor runs hot which shortens its life...", so i pointed out that windshield wiper motors run indefinitely without cooling. you didn't say anything about lubrication, which is an entirely different topic.

if you're trying to say that fuel pumps are not lubricated, then you're wrong there too - they use polymer bushings [like delrin] that are sufficiently lubricated by the fuel that fills the pump when it's used for the first time.

you can go ahead and believe in urban legend all you want, but the fact is that fuel pumps are fully internally saturated with fuel. any time they're working and generating heat, they're circulating that liquid and the heat is being carried away. [not that it's even an issue in the first place, but hey.] if there's insufficient fuel to circulate, the car's not going to work, and even if the ignition is left on, the pump will be switched off after two seconds by the engine computer if the engine stops running. thus, there is no situation in which heat can possibly be a failure mode for the typical modern fuel pump.

early fuel injection pumps did indeed fail regularly, but they were not the impeller types we see today. impellers don't have any touching parts and have nothing to wear - they are as reliable as the electric motor that drives them, and /that/ is reliable as its manufacturer wants it to be - you don't have any influence over it.

TRASH IT. You want nothing to do with reusing a mildly used and stored one. I shudder at the thought of being broken down in a bad part of town. Or along the side of a freeway where you can be killed by a drunk.

I hear all this reasoning but I also know that welders are very reluctant to weld fuel tanks. I had a tank out of a motor home and they insisted it be washed out completely with soapy water before he would weld on it.

I also know of a person that was going to weld on a fuel tanker truck at a shop next door to where I was working. He put dry ice ( or something similar) in the tank the night before to remove all the oxygen. The tank blew up the next day as he was welding. He was instantly killed and body parts were found over at our place of business. Perhaps a welding torch is different that fuel pump commutation sparks, but why take any chance at creating a fire or explosion?

In message , uncle_vito writes

I can't visualise a commutator running in neat petrol, even if there is no fire risk(which I doubt) the motor bearings would be washed clean with any fuel and would be liable to seizure.

In message , uncle_vito writes

I can't visualise a commutator running in neat petrol, even if there is no fire risk(which I doubt) the motor bearings would be washed clean with any fuel and would be liable to seizure.

At Fri, 22 Mar 2013 14:14:23 -0700, uncle_vito rearranged some electrons to write:

snipped-for-privacy@l9g2000yqp.googlegroups.com...

You would need to have oxygen in order to start a fire.

Be that as it is, I drive a 20-year old car with the original fuel pump, and lots of people that have cars half the age of mine have already replace the fuel pump on the same make of car, and they report driving around for days upon days, weeks on end for some, and the pump ultimately fails. Did the low fuel level cause the demise of the fuel pump? Who knows. But the very small data pool that I have says that habitual low fuel and fuel pump failures are related.

If you can avoid a $150-ish part by doing nothing more than filling the gas tank, why not do that?

If you are in the habit of driving around with the fuel level very low, then don't be alarmed that the pump fails. Just make the necessary repair and move on.

But the OP should sell the pump he has, and wait for the day that he needs to replace a fuel pump and then go out and buy one.

A windshield wiper motor and a fuel pump motor have little resembelence to one another after you get past the motor part. A fuel pump is a low torque, high speed motor. The windshield wipers use a high torque, low speed motor. A fuel pump directly pumps fuel, the windshield has a reduction gear to mechanically increase the power of the mechanism. The fuel pump runs as long as the car is on, more or less, the wiper motor runs much less. Apples and oranges....

since the fuel pump doesn't have wearing parts other than the motor component, the resemblance between both motor units is 100% relevant.

reduction gears mean that you can [and do] use a high speed low torque electric motor for the wipers.

you've never been to oregon or washington state in the winter then - in their rainy season, there is 100% correlation between fuel pump hours and wiper motor hours.

Nope, I disagree. There is a big difference between different types of electric motors, if not I'd be out a side gig. Fuel pumps spin much faster and always. Wiper motor not so much.

There is nowhere on earth that a windshield wiper motor runs anywhere near the duty cycle of a fuel pump motor. And, setting a windshield wiper motor under a panel where it remains dry, filling it with grease where it remains lubricated, and putting it behind a reduction gear where the mechanical advantage can be leveraged makes it entirely different than a motor that is submerged in gasoline where the lubricant is compromised, and the power of the motor is not leveraged with reduction gears.

A wiper motor is mucl closer to a window motor than to a fuel pump motor, although these motors are also quite different. The operating environment is similar, although the duty cycle is not even close. Lots of stuff is different, but the idea that the motors are located in dry locations instead of wet ones is the same, the lubrication lasts for decades is the same, there are reduction gear mechanisms which are similar, and so on.

The point being, a fuel pump motor lives in a hostile environment, and some of the hostility is used to the benefit of the motor if the fuel levels are kept high instead of being held low. The external presence of fuel surrounding the motor has a cooling influence. If the fuel level is held low for extended periods, the impact is that the motor runs hotter than it has to if it is submerged, and this additional heat shortens the life of the motor.

Perhaps the motor lasts 15 years instead of 20, or 7 years instead of 15, whatever. I'm driving a car that was built 19 years ago, has 150,000 miles on it, and the pump is the original. I keep the tank filled -- rather, when the tank gets to E, I fill it instead of just putting in a few dollars-worth of gas. In EVERY instance of fuel pump failure in cars of similar age as mine, or younger, the drivers report they let the tank remain below 1/4 for extended periods -- they drop in a few dollars-worth of gas to get to the next day or day after then repeat.

Is keeping the tank filled a guarantee that the pump will never fail? Probably not. But, why not fill the tank hoping to avoid early replacement of a part that is typically $150-ish to purchase, and often requires the gas tank to be removed from the car to replace?

On Tue, 26 Mar 2013 09:06:38 -0700, "Jeff Strickland" snipped-for-privacy@yahoo.com wrote:

Higher static head pressure probably eases the work the pump has to do, and more gas in the tank provides a bigger heat sink. So why not fill your tank when it hits 3/4 or 1/2 full? In the end it probably won't make a difference that can be measured. I don't buy the idea that running a car all the time with 1/4 tank is the main cause of pump failure. They just wear out, and some are built better than others, even the same pump model from the same manufacturer. Lemons, or almost lemons. First off, not many people don't fill up at the gas station. It's a big waste of time continually putting only a few gallons in a gas tank. I don't know anybody who does that. My son does, and in fact he's put new pumps on their cars. But they were high mileage cars anyway. Secondly, I've had 2 pumps fail on GM cars at about 120k miles, and the Lumina I'm junking has the original pump with 180k miles. All were gassed up the same - basically when it falls below 1/4 tank, fill it up. It's just initial quality of the pump. Not saying to run the pump dry, but how much gas you keep in your tank isn't something I'd ever worry about. BTW, a typical GM pump runs about 2.5-3 bills at auto parts stores. It's modular and comes with sending unit. You don't want to cheap out and try replacing only the pump. High hassle and high failure rate. Think I paid close to 5 bills when I had one replaced by a shop. The ones I've done myself took 4-5 hours to do, steady, careful and somewhat leisurely since there was no clock. That's with jackstands and creeper.

I like the redneck way. If you can do it, cut a hole in the trunk with a jig saw, replace pump and put a piece of tin back over the hole with pop rivits. Used to work on the freeze plugs also. Just use a hole saw from the inside on the firewall.

just use a large jug for gasoline on the dash board with a rubber hose that go to the carbo-rator, all gravity feed, no need for a stinkin pump anyway.

you guys.

store it in WD40...... like Grandma's undies......

I used to have a 1950 Ford tractor that worked that way. Gas tank set over the engine, copper line with a stopcock right to the carb. Worked great!

The Lumina tank wasn't under the trunk, but the back seat. Same with my Grand Am. Think the FWD cars use "contoured" tanks, and get more trunk space that way. Both those tanks were contoured and unlike the pillow shaped tanks aft of the axle in RWD cars. So you would cut through the floor under the rear seat. But pulling the tank might happen only once in the life of a car anyway, so I won't be cutting holes.

I think on vaccum carbs lots of lattitude to do this, plus that self regulating gas float valve on the carb.

but the injectors need 40 PSI across them, BUT could hook up the spair tire air on the roof with a valve and hose to a pressurized gasoline can and have tube come out the bottom to the fuel rail.

=> NO FUEL PUMP TO STORE in Grandma's WD40 again.

You'll get more redneck cred using an empty beer keg for the air pressure tank.

uncle_vito posted for all of us...

And I know how to SNIP

I believe they fill them with water and braze them.

Also there are pumps in the tanks correct?

also there ate are explosion proof motors correct?