1/4 full? I know a lot of people like to keep their tank 1/4, 1/3 (?) sometimes 1/2 full if at all possible. The logic was "because of all the debris on the bottom can clog up fuel filter." Now.. I can actually say that even when I had vehicles that required checking out the fuel line, etc (a few,) the fuel filter itself was NEVER the cause and the gas always seemed to pass flow test, even on an old one. Now this question is not about fuel filters, but rather if debris/dirt can even get ON the bottom of a fuel tank, if all that goes in is gas and cleaners...... ?
Any truth to "debris" on bottom of fuel tank, 1/4?
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AFAIK, fuel is being picked up by the fuel pump from the bottom of the tank, so even if your tank is full, the stuff at the bottom would get sucked in first.
The main reason it's advisable not to run on fumes is to protect the fuel pump. In some applications the fuel pump is cooled by the surrounding gasoline at the bottom of the tank. Now, if there is very little fuel left, the pump is not submerged and may overheat and fail prematurely, but personally I never had that happen to me either.
The main reason it's advisable not to run on fumes is to protect the fuel pump. In some applications the fuel pump is cooled by the surrounding gasoline at the bottom of the tank. Now, if there is very little fuel left, the pump is not submerged and may overheat and fail prematurely, but personally I never had that happen to me either.
I replaced the original in tank fuel pump on my old van at 180,000 miles. The 'sock' was clean and there was almost zero dirt in the tank. I was prepared to have to some how clean the tank. But all I did was rinse/slosh it out with a little gas.
I think the dirt in the tank is one of the problems from decades ago that usually is no longer a concern. But I have heard that keeping some gas in the tank cools the pump.
I think the dirt in the tank is one of the problems from decades ago that usually is no longer a concern. But I have heard that keeping some gas in the tank cools the pump.
I don't think that debris in the fuel tank is an issue for any car in regular use.
In cars that have been stored for long periods, like years, debris can come from either corrosion in the tank, or deterirating tank lining material.
Also, IIRC, the electric fuel pump is cooled by the passage of fuel through it, not by its immersion in fuel.
It is therefore never good to run the tank dry, since this may damage the pump and shorten or end its life.
FWIW, I consider the car's tank capacity as there to be used and I generally refill at a point where the tank will take all but a couple of gallons of its rated capacity.
This is safe with any car you are familiar with, since you develop a very good idea of what the fuel gauge really means at any given point.
In cars that have been stored for long periods, like years, debris can come from either corrosion in the tank, or deterirating tank lining material.
Also, IIRC, the electric fuel pump is cooled by the passage of fuel through it, not by its immersion in fuel.
It is therefore never good to run the tank dry, since this may damage the pump and shorten or end its life.
FWIW, I consider the car's tank capacity as there to be used and I generally refill at a point where the tank will take all but a couple of gallons of its rated capacity.
This is safe with any car you are familiar with, since you develop a very good idea of what the fuel gauge really means at any given point.
Wouldn't the filter on the gas pump catch most of the dirt ?
I always get gas before my dash light comes on.
I always get gas before my dash light comes on.
Lots of cars have plastic tanks now. The new injection systems have "non-return" one line systems where the pump is controlled by the ECU in direct relationship to demand. The old systems were shunt regulated and excess gas was fed back to the tank. Those pumps worked a lot harder. Volvos had a "prepump" in the tank and an expensive Bosch pump outside. I have several hundred K on a Toyota which I often let run down to the red light. No problems and origonal filter still in place.
As I recall, the FAA now allows pump gas to be used in some aircraft-- it has to be clean to meet car fuel injection standards.
As I recall, the FAA now allows pump gas to be used in some aircraft-- it has to be clean to meet car fuel injection standards.
When talking large 10,000 gallon transfer tanks you'd be surprised how much "stuff" accumulates on the bottom. They check for water every time they fill them and some fuels even support algae growth and need to be treated. Since fuel is refiltered at the dispenser you will only get a very small dose of particulate and some water which may accumulate while the vehicle is at rest. When pumping into your tank at the next fill you would stir that stuff up. Or how about this, have you ever pulled in your driveway and shut off your car and heard the fuel 'sloshing' back and fourth. What i am getting at is there are obvoius negatives to running the tank empty but as far as down to an eigth i dont think you will have a significant amount of debris in your tank. Equipment on jobsites get more dirt, dust, and debis in their tanks then our passenger cars fueling up in clean and controlled conditions.
I agree is pretty much a non issue now days. The only time i have see problems are when the fuel sits for a long time, especially diesel.
I would imagine diesels would have more problems, if any, than gassers. Especially with little algae
One thing I like about RaceTrac gas stations is that I see the contractor changing the filters on the gas pumps on a regular basis. The filter is about the same size as the FL-1A oil filter.
near us a Racetrac is an excellent choice. Cheap and very busy. That's what we look for when we buy gas for our fleet trucks.
I changed out the gas tank on the wife's '99 Sentra (aka the Black Lemon of Craigslist) at around 130,000 miles.
I didn't notice any debris in the tank and the fuel pump sock was clean.
I didn't notice any debris in the tank and the fuel pump sock was clean.
I changed the fuel filter, which is part of the fuel pump assembly, in my car a couple days ago and I was surprised at how clean the bottom of the tank looked with the car being 10 yo and 112k miles. I'm one of those people who perpetually drives until the light comes on and fills up with whatever is cheapest or most convenient.
I replaced the fuel pump several times in my 93 Suburban and the tank was always spotless. The only dirt that got in there is dirt from me replacing the fuel pump and that was not much at all.
Now leave the vehicle sit for a year or two and the tank will be incredibly dirty.
Now leave the vehicle sit for a year or two and the tank will be incredibly dirty.
Back in the 80's there was considerable junk in the fuel.
The bowsers had little glass rotating indicators that the fuel passed through on the way to the nozzle, and there was nearly always a very small (to very significant) amount of sediment in it...my job as a kid was to identify the clean ones, or suggest another station.
The inline filters in the fuel line to the fuel pump always had sediment (and water droplets) in the bottom, and when you drained the tank there would be maybe a teaspoon of really fine silt would be swishing around the bottom.
With my F.I. vehicles, when I reverse drain them into a pan on changeout, there's always red junk comes out.
The bowsers had little glass rotating indicators that the fuel passed through on the way to the nozzle, and there was nearly always a very small (to very significant) amount of sediment in it...my job as a kid was to identify the clean ones, or suggest another station.
The inline filters in the fuel line to the fuel pump always had sediment (and water droplets) in the bottom, and when you drained the tank there would be maybe a teaspoon of really fine silt would be swishing around the bottom.
With my F.I. vehicles, when I reverse drain them into a pan on changeout, there's always red junk comes out.
Yeah, I always get [censored] out of my filters on reverse drain. I change them every 25-30k.
I dont fear going below a certain % as 'bad' for it. However, I refill at 1/2 as the bottom half is my reserve.
I dont fear going below a certain % as 'bad' for it. However, I refill at 1/2 as the bottom half is my reserve.
Debris DOES settle to the bottom.
Whether empty or full, that's where any will be.
What good is full or 1/4 full for this?
I usually just ill it up, then drive till it's way down.
Whether empty or full, that's where any will be.
What good is full or 1/4 full for this?
I usually just ill it up, then drive till it's way down.
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I get to a 1/4 tank then fill up. Its not about junk or debris it's about having enough gas to get to a gas station w/o worries. Honestly I really don't know how accurate the gas gauge is, and don't want to find out. I'd rather not make a hard turn or some kind of emergency stop or maneuver and risk sucking up air instead of fuel. I also own two older vehicles that use fuel to cool the fuel pump, and would rather not gamble with running low on fuel. Opinions vary.
Originally Posted By: SteveSRT8
near us a Racetrac is an excellent choice. Cheap and very busy. That's what we look for when we buy gas for our fleet trucks.
I have used racetrack on all our cars since they were new. I replaced fuelpump on my 1996 explorer and 2002 maxima at about 150k miles each. Both tanks were absoutley spotless when I looked inside.
near us a Racetrac is an excellent choice. Cheap and very busy. That's what we look for when we buy gas for our fleet trucks.
I have used racetrack on all our cars since they were new. I replaced fuelpump on my 1996 explorer and 2002 maxima at about 150k miles each. Both tanks were absoutley spotless when I looked inside.
Originally Posted By: Quattro Pete
AFAIK, fuel is being picked up by the fuel pump from the bottom of the tank, so even if your tank is full, the stuff at the bottom would get sucked in first.
The main reason it's advisable not to run on fumes is to protect the fuel pump. In some applications the fuel pump is cooled by the surrounding gasoline at the bottom of the tank. Now, if there is very little fuel left, the pump is not submerged and may overheat and fail prematurely, but personally I never had that happen to me either.
Originally Posted By: mechtech2
Debris DOES settle to the bottom.
Whether empty or full, that's where any will be.
What good is full or 1/4 full for this?
I usually just fill it up, then drive till it's way down.
People that think letting the tank get below 1/4th full will suck up the stuff on the bottom of the tank obviously don't know how a fuel pump works in the first place. It's sucking up fuel near the bottom AT ALL TIMES!
As stated previously, the main reason why it's recommended to keep the tank from getting dry is to cool the fuel pump (if it's internal) but even then, the auto manufacturers prevent this by leaving a gallon of gas in the tank even when your gauge says you're empty.
It's an old wife's tale that doesn't apply today with high quality control at the gas pumps as well as your car's lifetime fuel filter.
It's the people who forget to close their gas caps and end up driving around with it wide open, allowing for stuff to get in the tank that started this MYTH!!
AFAIK, fuel is being picked up by the fuel pump from the bottom of the tank, so even if your tank is full, the stuff at the bottom would get sucked in first.
The main reason it's advisable not to run on fumes is to protect the fuel pump. In some applications the fuel pump is cooled by the surrounding gasoline at the bottom of the tank. Now, if there is very little fuel left, the pump is not submerged and may overheat and fail prematurely, but personally I never had that happen to me either.
Originally Posted By: mechtech2
Debris DOES settle to the bottom.
Whether empty or full, that's where any will be.
What good is full or 1/4 full for this?
I usually just fill it up, then drive till it's way down.
People that think letting the tank get below 1/4th full will suck up the stuff on the bottom of the tank obviously don't know how a fuel pump works in the first place. It's sucking up fuel near the bottom AT ALL TIMES!
As stated previously, the main reason why it's recommended to keep the tank from getting dry is to cool the fuel pump (if it's internal) but even then, the auto manufacturers prevent this by leaving a gallon of gas in the tank even when your gauge says you're empty.
It's an old wife's tale that doesn't apply today with high quality control at the gas pumps as well as your car's lifetime fuel filter.
It's the people who forget to close their gas caps and end up driving around with it wide open, allowing for stuff to get in the tank that started this MYTH!!
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