when to fill up?

[yostumpy]

ok folks, i'll give 1/4 tank a try!

[Kincurd]

I have 13.4 gallon tank, and I always fill all the way up and wait until I get the empty light before refilling.

Ideally though, the less weight you drive with the better. Some people even mod their cars to have a smaller tank, so they forcibly run with less weight on a full tank.

I say, just fill 'er up, and unless you're willing to go to extremes, don't worry about it beyond that. You need to use a full tank every time you fill up to accurately and easily calibrate your Scangauge, anyway.

Once you get to a point where you're getting twice as much MPG as stock, then you can start half-filling and maybe thinking about getting a half tank or something.

If I had a garage and was getting really bored, I might consider syphoning my excess gas into a 50-gal drum but until then...

[Diesel_Dave]

To each his own, but I run mine down to almost completely empty. This is for three reasons.

1) More accurate mpg numbers
2) It's a game with myself to see how many miles I can get out of a tank
3) I have a tank that nominally holds 34 gallons. The grocery store I use (Kroger) gives me a discount on one fill up per month up to 35 gallons. If I run till empty I can go all month on one tank and 35 gallons fills me up into the filler neck. In the last 7 months I've driven 7,853 miles on 7 tanks.

I've never run the truck out of fuel, although once I had it in the shop and they ran it out while test driving it. That's not something I care to repeat--every so often some air would hit the injectors and it would stumble & studder. It took a week or two for the intermittent symptoms to go away.

[gone-ot]

Originally Posted by Diesel_Dave

...

1) More accurate mpg numbers

2) It's a game with myself to see how many miles I can get out of a tank

3) I have a tank that nominally holds 34 gallons. The grocery store I use (Kroger) gives me a discount on one fill up per month up to 35 gallons. If I run till empty I can go all month on one tank and 35 gallons fills me up into the filler neck. In the last 7 months I've driven 7,853 miles on 7 tanks.

...let me "back-pedal" here for a moment and say that I agree 100% with #1 above...especially when attempting to "calibrate" my SGII for the first time. However, once I have things "dialed-in" I revert to 1/4-tank threshhold:

1) to eliminate "running OUT of gas" anxiety.
2) ensure the wife won't run it "empty" accidentally.
3) guarantee the in-tank fuel pump is NEVER exposed.

...hence, almost ALL my fill-ups measure around 300 miles, because typically I can easily get 100-miles per 'each' 1/4-tank mark on the gas gauge. However, on LONG trips, it's 400 miles between fill-ups, because of the better highway MPG's.

...here in Tucson, it's FRY's, instead of Kroger's, but same "food-for-gas" scheme.

[Diesel_Dave]

Originally Posted by Old Tele man

...here in Tucson, it's FRY's, instead of Kroger's, but same "food-for-gas" scheme.

Never thought of it that way. Sort of like the corrupt oil-for-food program with Sadaam Hussein.

As far as the accuracy goes, I know it is better to do it in 35-gallon increments. The thing is, it takes me 3 months to do an A-B-A test with hand-calculated mileage. That introduces other sources of variation (weather, etc.).

[slowmover]

When it drops below half-tank is my preference. Usual range is above 700-miles per tank town or country. But having lived in tornado & hurricane country all my life has sensitized me to being low on fuel, ever, as being a mistaken habit.

There are days and drives I don't care to have to think about where to buy fuel (additive quality & freshness), and, as I try to combine trips, my choices when around town are such that I prefer the luxury of fueling when and where I choose. Thus to fuel is as much an errand as any other, and deserves being included with other stops. Rather, other stops may remind me that I'll passing by a favored fuel location, thus -- if under half -- an easy time to keep the tank topped off.

.

[user removed]

Recnetly with the rising gas prices, I have used my 3@5 gallon fuel cans to stock up on fuel. Last stop it was $95.15. 15.8 gallons in the car and 10 gallons in my extra tanks.
That gives me a 15 gallon inventory above the full tank in the car. In the 2011 CBR that 15 gallons at 75 MPG, gives me a combined range of right at 1575 miles. That depends on the weather, since I avoid riding the bike in the rain.

Here we also have to deal with hurricanes and potential power outages that can last as long as a week, even closing the gas stations unless they have auxiliary power.

I try to fill the cans with precisely 5 gallons each so I can still keep track of my mileage, and when I post to my garage I will break the total consumed into two separate fills to keep my average tank miles close to correct.

regards
Mech

[larrybuck]

It seems strange to me that no one has mentioned that CRUD could be at the bottom of the tank, which we don't want clogging the pick up.



Never had a problem w Japanese motorcycles on switching from main to reserve,
but on a past Harley; huge pain of kicking, and kicking, and kicking! Sweaty!

new (low miles) '75 FX 1200 Superglide.

I was just picturing Frank getting a green stick fracture to his leg, had his friend
needed to lock up the brakes for a dog or something.

PS. I love the idea of that perfect long tank mpg figure, but crud potential would always be in the back of my mind.

[gone-ot]

...with todays electric fuel pumps being physically located in the very bottom of the tank, crud is there, around the pump, ALL the time (albeit in differing proportions) whether the tank is full or empty.

[Diesel_Dave]

Also, many modern tanks (including mine) are now plastic rather than metal. While it doesn't eliminate the crud it does reduce it as much of the crud is rust flakes coming off the inside of the tank over time.