Running car on empty tank

[miniyazz]

Personally I don't drain the tank because it's an old car and may have heavy contaminants (e.g. metal filings stuff) at the bottom of the tank, and draining it would increase the chance of those damaging the engine.

You've got a fuel filter which will stop these getting into the engine.

Running it almost empty will pull all the crap through out the bottom of the tank, the fuel filter should stop it getting through but then its blocking up the fuel filter. Fuel filters are designed to filter fuel particles and general crap out of fuel, they are not there so you can run it empty

Myth! The amount of movement a tank sees there is no way that kind of accumulation would occur. Besides which, as I understand it, tanks might have the exit at the top but a plumbed internally to draw fuel from the bottom of the tank...?

So - here's a few conflicting thoughts on whether or not driving with an almost empty tank is bad, and why. What do the rest of you think on the matter?

 

[ajgoodfellow]

I wouldn't - I ran out of fuel in my MG and I wasn't convinced it was OK afterwards until I replaced the fuel filter. Could just be in the mind though!

I've heard that it's a really bad idea in modern diesel engines though!

 

[InvaderGIR]

Old diesels is a bad idea, as you then have to fill the fuel system, normally by a balloon pump in the engine bay.

As for petrol cars, doesn't make much of a difference, you have a filter to stop crap, but also the fuel pump is at the bottom of the tank anyway, so any crap will go in there whenever it wants, not when it's empty.

 

[shauncr91]

I normally run my tank all the way to the fuel light (I'm a poor student + very tight with money), and tbh I've never really given it a second thought. Never heard anybody warn that running it on a low tank would cause harm...

Wouldn't most of the rubbish go there anyway regardless of fuel level? Anything in there will most likely be metal and since the tank lets fuel out of the bottom, mavity would just force it there anyway. Not like metal is going to float in there is it?

 

[Jokester]

Yep, the takeoff is at the bottom, otherwise you wouldn't get most of the fuel out of the tank...

 

[InvaderGIR]

Fuel light is still a gallon in there (according to a vast majority of people here in an old fuel thread), that's not empty...empty is when it stops running.

 

[ajgoodfellow]

I also routinely wait for the fuel light to come on before filling up, although I've only actually ran out once, touch wood!

 

[ajgoodfellow]

Fuel light is still a gallon in there, that's not empty...empty is when it stops running.

Just what I was thinking!

 

[InvaderGIR]

I've never run out of fuel...used to be quite ***** with it too. But I did get enough crap in my filter to block the fuel line.

 

[MrMatteh]

my fuel pump is on the top of the tank, so it would never get *all* of the fuel out

also, the inside of my 1992 clio's tank is completely spotless

 

[InvaderGIR]

So you have a pipe going down into the tank, or coming off the bottom of the tank?

 

[MrMatteh]

it sits like this:

http://i189.photobucket.com/albums/z18/Matteh449/DSCF1686.jpg

 

[Clarkey]

fuel pickup (normally) has a pre-filter on anyway along with the main filter, no need to worry about anything getting pulled through.

 

[PhillyDee]

When I bought my Rover Streetwise (Shut up you lot . . . . I like it ) the garage didnt even leave enough fuel in to get to the nearest petrol station. So it coughed and spluttered and had to walk to the garage. After a long run (roughly 1.5hours) in the car it exhibited the same symptoms as running out of juice so I called the RAC. Didnt find a fault and the car ran fine. It done it 3-4 times after that after a long run (about 1.5 hours, then half an hour after that etc...) till I replaced the fuel filter (Which was VERY manky). Its never done it since. So yes, you can run it till its empty, just change the fuel filter if it stops running. At least I know my car doesnt have a fuel light . . . .

 

[InvaderGIR]

it sits like this:

http://i189.photobucket.com/albums/z18/Matteh449/DSCF1686.jpg

Ah, cool, effectively a pipe into the tank...looks like I'm wrong for some cars.

I know my R5, 306, 205 all had pumps at the bottom of the tank, and I think the Sierra did too, figured most would be the same, as pulling fuel up is harder than letting it flow down.

 

[miniyazz]

In that case, perhaps I'll not worry so much about letting it get to empty. I carry a spare 5l container of petrol just in case, anyway, so actually running out of fuel would be an inconvenience not a disaster.

Who else carries round a few litres of spare fuel, just in case?

 

[InvaderGIR]

All my family members do, I don't as I always make sure I have enough fuel, and I also don't like the idea of a 5l container of fuel flying about in the boot of my car.

 

[MrMatteh]

Ah, cool, effectively a pipe into the tank...looks like I'm wrong for some cars.

I know my R5, 306, 205 all had pumps at the bottom of the tank, and I think the Sierra did too, figured most would be the same, as pulling fuel up is harder than letting it flow down.

unless your tank is higher than your injectors, it would have to do it eventually

 

[InvaderGIR]

Hehe yeah, but I meant at the tank end. I more saw the pump as a means to get the fuel to the front of the car, rather than out of the tank...if that makes sense.

 

[Tee Hee Johnson]

Doesnt bother me much... i usually run till it really needs it!

I guess thats what the filter is for... catchin anything Im sure i did read/hear a while back that running on empty was bad as the flow of petrol can be interrupted, which would be bad!