My sister-in-law continually runs her gas low and had to replace fuel pump. Mechanic told her to keep at least a quarter of the tank full to cool the pump. Is that correct? Thanks
1/4 is a good point to refill. 1/8 should be fine also if the gauge is some what correct. And the mechanic is giving good advice. He probably said 1/4 because he suspects that she will let it go lower before refueling. And yes the fuel acts as cooling agent.
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A mechanic told me that condensation forms inside the tank and can cause problems if the fuel level is at 1/4 for a while.
The reason to keep it about 1/8 full is because the pump is submerged in the tank, and the gas is used to cool the pump when it’s running. When it gets too low the pump can burn out because it’s running too hot.
I think this is the key. Running low (say 1/8 tank) now and then shouldn’t be a problem, but doing it ‘continually’ is.
As long as the pump is not inhaling air through the fuel pump then the fuel level is irrelevant.
Of course if it’s inhaling any air the engine will buck.
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I try to never let the fuel level get below 1/2, because that way I can stop for fuel when it’s convenient, and where the price is good. It also helps keep the fuel pump from overheating or wearing out prematurely.
My car has 3+ gallons lef after 500+ miles. If I am on a trip, I don.t want to stop twice as often for gas.
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I’ve always assumed this as well, although I’ve heard others (some were mechanics) say otherwise. I really don’t know, but it seems silly to provide extended range fuel tanks if you have to refill them before they’re near empty.
I’m afraid to say it out loud, but I’ve been lucky with fuel pumps. I have two GM vehicles, both 2005’s with a little over 150k miles each and haven’t had to replace a fuel pump yet. My 1998 Dodge Ram went over 190k on a single fuel pump. My wife’s 99 Camry went 198k on one fuel pump. 08 Malibu, 100k, then traded it. 2013 Highlander 108k, still have that. I did have to replace a mechanical pump on a square body Chevy truck that I was borrowing from my dad, but that’s the only fuel pump I’ve had to replace so far. I dread replacing an in tank pump, but I’m sure I’m due a failure. I generally fill up below 1/4 tank, but rarely let the level drop until the fuel light comes on (if equipped).
For decades I’ve regularly let the gas gauge drop to pretty much Empty, and have never replaced a fuel pump.
I’ve always been known to run a tank down to fumes before refilling. I’ve never had to replace a fuel pump in my life, even on vehicles with as much as 270k miles on them.