Re: Gas Mileage-Fuelly Reply #25 – February 10, 2017, 05:30:38 pm "Full when I head out AND Full when I come back home."For myself, I'll add "...and full (or close to it) when I pull into a campsite."
Re: Gas Mileage-Fuelly Reply #26 – February 10, 2017, 05:50:10 pm "That way you won't have to worry about sucking the crud from the bottom and destroying your fuel pump, one of the main reasons for their failure. "I have heard this comment about sucking from the bottom many times but don't see it as an issue. The pickup line in the tank does not float (as far as I know) and, thus, is always sucking from the bottom of the tank. Unless the crud floats on top of the fuel, there is no more crud being sucked up at 1/4 tank than there is at a full tank. Am I missing something?Monti
Re: Gas Mileage-Fuelly Reply #27 – February 10, 2017, 07:36:59 pm I drive on the top 1/2-2/3 of the tank because I can't push this rig if I run out and having to call CoachNet for running out of gas would be downright humiliating! As Monti said, fuel pumps suck gas from the bottom of the tank, so whether the tank is a quarter full or half full or completely full, the bottom is the bottom. The fuel pump does rely on being immersed in gas to cool it, though; I don't know the actual number of gallons in a 55-gallon gas tank that would keep the pump functionally "submerged", but there are mechanics on this board who do, I'm sure! Additionally, I think that the fuel pumps on "modern" engines have little screens or "sock" filters to catch any debris, and the fuel filter (More Information for MOTORCRAFT FG986B) also removes particles and crud that may be in the fuel. Between the two (?) filter systems, I believe the gas that gets to the "burn point" is pretty clean! (Engine gurus, please correct any misinformation; thank you.)Joan
Re: Gas Mileage-Fuelly Reply #28 – February 10, 2017, 08:06:51 pm I make no claim to this being accurate but my hubby says the reason to not always drive around close to empty is the relative concentration of the crud going into the fuel filter, pump and finally engine. Yes there is always some crud in the tank, but it is a relatively small proportion (lower concentration) when the tank is full compared to an empty tank when the crud will be quite concentrated and more likely to gum things up.
Re: Gas Mileage-Fuelly Reply #29 – February 10, 2017, 09:35:32 pm "...I think that the fuel pumps... have little screens or "sock" filters to catch any debris, and the fuel filter... also removes particles and crud that may be in the fuel.Correct JCT! On both of the two occasions when I had to replace my fuel pump/s I was informed that the most frequent cause of pump failure was the clogging of the 'sock' filter which encloses the intake to the pump. Also in those explanations was the admonishment to not let the tank be drawn too far down due to the fact that clogging of that 'sock' would be the result. One of the early symptoms of an impending pump failure is stumbling or hesitation of the engine. I also experienced this shortly after taking on gas at a remote station in Canada (my after thought was that that gas was contaminated). It wasn't until much later that the pump finally quit.
Re: Gas Mileage-Fuelly Reply #30 – February 11, 2017, 12:07:07 am I've checked my gas gauge a number times, and there is at least 6 gallons in the tank when the needle is directly on empty (about 50 miles of travel), and about 100 miles of travel between 1/4 tank and the empty mark. I have no qualms about running down to 1/8 tank by the next gas station, and close to empty if going another 20-30 miles gets me home. I generally will fuel up any time a good opportunity (low price, easy access, etc) comes along below 1/3 tank, and we always fuel up for the night unless we can plug in so we can run the generator if we need to.In areas with high temperatures during our travel, I do not let the level fall below 1/3 tank, so I can run the A/C if we get stopped somewhere unexpectedly.Hey, I'm a glider pilot - we live on the edge constantly while flying
Re: Gas Mileage-Fuelly Reply #31 – February 11, 2017, 07:47:58 am Hey Eric"I've checked my gas gauge a number times, and there is at least 6 gallons in the tank when the needle is directly on empty (about 50 miles of travel), and about 100 miles of travel between 1/4 tank and the empty mark. I have no qualms about running down to 1/8 tank by the next gas station, and close to empty if going another 20-30 miles gets me home"Your post reminds me of the episode of Seinfeld where Kramer was test driving a new car for Jerry. He wanted to see how far he could drive when borrowing Jerry's car so he wouldn't have to waste money on expensive fuel.I always wondered why people run out of gas, like were they so busy on the phone or does the fuel gage not work? Who knew it was a sport? Regarding fuel pump failures and low fuel levels, I seem to recall on the "Click & Clack" radio program them saying that low fuel tank levels contribute to fuel pump failure of in the tank fuel pumps. Their explanation was that the fuel actually helps keep the pump cool and low fuel and even worse, running out, can overheat the pump. Fact or fiction? I see no reason to play russian roulette with my fuel level. As Joan would say, "YMMV"Sreve K.
Re: Gas Mileage-Fuelly Reply #32 – February 11, 2017, 10:28:02 am Our (USA) gas system is a 'wet' system IE water is introduced in the system. Most states have an inspection system to insure 'pure' or as 'pure' fuel as you can get. In Oregon we do not. We have a system to insure correct volume but not correct 'pure' fuel. Water can be introduced. So maybe the 'crud' at the bottom of the tank is water.
Re: Gas Mileage-Fuelly Reply #33 – February 11, 2017, 12:15:33 pm Quote from: Steve K. - February 11, 2017, 07:47:58 amRegarding fuel pump failures and low fuel levels, I seem to recall on the "Click & Clack" radio program them saying that low fuel tank levels contribute to fuel pump failure of in the tank fuel pumps. Their explanation was that the fuel actually helps keep the pump cool and low fuel and even worse, running out, can overheat the pump. We have winner, the fuel pump is cooled by the gasoline surrounding it. This is especially true when driving in hot weather.The fuel pump has its own pre-filter, which prevents junk from entering, plus, as Monti pointed out, the pickup sits above the bottom of the tank.If there is enough water and/or debris, floating around inside the gas tank, that can reach the fuel pump's intake, you have bigger problems.Water, accumulating at the bottom of the tank, is a bigger problem than crud. It is caused by either condensation in the tank or by getting a bad batch of contaminated fuel. Water and the fuel pump do not play nice together.A preventative is to occasionally run a can or two of water remover in the tank .It is basically non-hydrated alcohol, which is water loving and will attach to water molecules, helping to remove them.Amazon.com: HEET 28201 Gas-Line Antifreeze and Water Remover, 12 Fl oz.:...Larry As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Re: Gas Mileage-Fuelly Reply #34 – February 11, 2017, 01:49:30 pm Quote from: Larry Wade - February 11, 2017, 12:15:33 pm"...Water, accumulating at the bottom of the tank, is a bigger problem than crud. It is caused by either condensation in the tank..."My dear ol' Grandma was a sharp women. She told me years ago to keep your gas tank as full as possible to prevent water accumulation through condensation and the formation of rust in the tank.Wisdom is what gets passed down. Knowledge and experience are the seeds of wisdom. Rats! All those naps in class didn't do me a bit of good. And where the heck did I put my smart pills?Kent
Re: Gas Mileage-Fuelly Reply #35 – February 11, 2017, 02:21:22 pm Quote from: Kent Heckethorn - February 11, 2017, 01:49:30 pmRats! All those naps in class didn't do me a bit of good. And where the heck did I put my smart pills?I keep mine in my COFFEE cup!
Re: Gas Mileage-Fuelly Reply #36 – February 11, 2017, 04:34:34 pm "We have winner, the fuel pump is cooled by the gasoline surrounding it. "This is especially true when driving in hot weather.LarryYipee, I win!Larry, I forget, what was the prize? I hope it's something for my LD like a new set of roof marker lights (round ones for an '03, or a can of Kwikee electric step lube. Steve K.
Re: Gas Mileage-Fuelly Reply #37 – February 12, 2017, 04:50:38 pm Quote from: colddog - February 11, 2017, 10:28:02 amOur (USA) gas system is a 'wet' system IE water is introduced in the system. Most states have an inspection system to insure 'pure' or as 'pure' fuel as you can get. In Oregon we do not. We have a system to insure correct volume but not correct 'pure' fuel. Water can be introduced. So maybe the 'crud' at the bottom of the tank is water.well if there is water at the bottom of the tank that is what is going to the engine. As has been stated all these fuel pumps are bottom feeders.(How else could they work ?) The only exception is the generator which feeds up 2-3 inches from the bottom.Garry
Re: Gas Mileage-Fuelly Reply #38 – February 12, 2017, 10:29:01 pm Quote from: Larry Wade - February 11, 2017, 12:15:33 pmWater, accumulating at the bottom of the tank, is a bigger problem than crud. It is caused by either condensation in the tank or by getting a bad batch of contaminated fuel. I've wondered if ethanol in the fuel will absorb water, carry it along when pumped to the engine, and disappear out the tail pipe, sort of like I imagine Heet, etc does. Because all the fuel I use in the RV has ethanol in it, I stopped adding the occasional can of Heet stuff long ago. No problems in over 25 years, and about 230,000 RV miles with the Ford V10.
Re: Gas Mileage-Fuelly Reply #39 – February 13, 2017, 01:34:53 am Quote from: Kent Heckethorn - February 11, 2017, 01:49:30 pmMy dear ol' Grandma was a sharp women. She told me years ago to keep your gas tank as full as possible to prevent water accumulation through condensation and the formation of rust in the tank.In the past, fuel tank condensation was a serious problem before the fuel systems were sealed.Today, it isn't as big an issue. More water is ingested in the fuel.Larry
Topic: Gas Mileage-Fuelly (Read 818 times)
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Topic: Gas Mileage-Fuelly (Read 818 times)
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