running your car til it's empty - bad ?

I killed a petrol fuel pump by trying to start it with no fuel in. The pump relies on the fuel for lubrication (not much with petrol though to be fair) and to keep it cool.
 
One of my first cars, the fuel pump suction went - it was rubber. Dont think thats related, I cant see how rubber would really need petrol as lubricant as its a solvent really.
Ive always run cars low, modern injection engines will lower the revs gradually so thats warning enough for me :D
Your'll go round the corner and 6k revs is no good and thats when you really are down to a wine glass of fuel. No harm done, just there wont be the fuel pressure so it'll hit a virtual limiter
 
I think the crap in the tank thing comes from older cars. Where they had rusty filler necks which dropped into the petrol.
 
AcidHell2 said:
Nope even the tank on my 1989 honda mtx was plated on the inside and had no rust.
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My Honda Superslug 250 had such a rotten tank that it wouldn't hold fuel anymore after I took it off and wire brushed it!

If this was never a problem, the special epoxy coatings you put inside the tank probably wouldn't be worth selling...
 
silversurfer said:
Your'll go round the corner and 6k revs is no good and thats when you really are down to a wine glass of fuel. No harm done, just there wont be the fuel pressure so it'll hit a virtual limiter
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Actualy fuel injection pumps rely on fuel to cool and lubricate the motor (the fuel actualy runs through the inside of the motor) so running it dry is not a good idea.
 
Its the misfire and igniting of the fuel in the exhaust that will cause damage to the cat.

The fuel lubricates the gears inside the pump
 
AcidHell2 said:
Never owned a diesel, why don't they like being run dry?
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some diesel pumps use the diesel to lubricate the pump on its way through so running dry = no lubrication = knackered pump if done too often.
 
AcidHell2 said:
It is. Anyone with a motorbike with a top mounted filler can tell you how much crud tanks have in them. There spotless. Tanks are lined and fuel these days are incredibly clean.
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or if u have a car, with pump removed and drop your spanner into it and spend a few mins fishing it out. lovely and clean in there, just a bit cold!
 
Snow-Munki said:
Hi,

Have been told 2 things that running the car til it's totally empty is both good and bad ??
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Well running it until it's totally empty is bad because it'll stop, and then you may have to push! :D
 
Never had a problem at all with my old car, but 2 weeks after i had started letting the fuel go right down, the car would sometimes lose power in first or second gear briefly and the car's rev's at idle sometimes kept going up and down between about 500rpm to 1000rpm. I'm going to guess its a bad thing and now i try to keep the fuel always at a quarter tank or more.
 
Gaygle said:
Never had a problem at all with my old car, but 2 weeks after i had started letting the fuel go right down, the car would sometimes lose power in first or second gear briefly and the car's rev's at idle sometimes kept going up and down between about 500rpm to 1000rpm. I'm going to guess its a bad thing and now i try to keep the fuel always at a quarter tank or more.
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Yeah, it'll be sludge, probably in the fuel filter. That'd be the first call of maintenance anyway, because it's the cheapest part to replace. the lumpy idle speed is called "hunting" and this is where the engine cannot maintain a stable idle speed, so it hunts to try and find one. Probably because of mild fuel starvation.

my advice would be to get a new fuel filter and a good fuel system flush/injector cleaner fluid.
 
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