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jplante4's avatar
jplante4
Explorer II
Feb 04, 2016

Fuel

I spent the best part of last year trying to figure out how many miles I can go before filling up. There turns out to be too many variables, and I should have just stuck with my usual metric of "add fuel at 1/2 tank".

I had it figured at 85 gallons every 800 miles. Now, that 800 miles is actually 740, because I switched from 9R22.5 GY tires to 255/70R22.5 Yokos. That worked out to about 8.5 MPG, which I figured was average for a CAT 3126 300 HP. Oh, did I mention this is my first diesel anything?

Additionally, I had a plugged fuel tank vent which prevented me from getting a good fill-up. So add up all these factors and accumulate the errors over a year and 6000 miles and, voilĂ , you run out of diesel.

Coach-Net was great, but I had a hard time getting them to understand where I was, even though it was straight forward (I-10 west Florida mile marker about 40). When the service person called, I had to clarify where I was. Coach-Net had her going the opposite direction.

Anyway 2 hours and 95 gallons of diesel fuel later (100 gallon tank) and I'm back on the road. Lesson (re-)learned: Add fuel at 1/2 tank on the gauge.

9 Replies

  • I figure my mileage at 10mpg. Sometimes I get more and sometimes less. I have 85+ gallons so somewhere between 700 and 800 miles I start looking for fuel, but it might take several days. 800 miles is about 3 days of driving plus however long I stay in each place. Im on a tight schedule (not)
  • (Timely post. I'm broke down over a week now because of a fuel issue).

    Anyways, we make it somewhat of a game looking on gas buddy of where not to fuel up if possible. And we know how far we can go little over 300 miles on full tank. And over 500 not towing.

    Back to fuel problem I'm having. Sending unit went out. Replaced with new (aftermarket) sending unit. Not strong enough or draw straw is to small.

    What a mess the screen was on old sending unit. We think we are buying good clean fuel but bottom of screen was real dirty. Then again 16 years old probably has something to do with it.

    The new suction draw tube kit (to bypass sending unit) says to install tube 1 inch from bottom of tank. When ordering over the phone, guy says people that have been installing for sometime lay 4 or 5 quarters on bottom of tank to use as spacer. Sounded good to me.
  • I begin looking for a place to fill up when the gauge hits half tank and definitely before 1/4 tank.

    Works out to about 300 miles in my truck while towing. Perfect time to stretch my legs.
  • wolfe10 wrote:
    Suggest you change both fuel filters-- sucking fuel off the bottom of the tank will tend to clog filters.

    And, your manual primer pump made priming/starting a LOT easier.

    BTW, this is also hard on the whole fuel system, as fuel is used to cool and lube injection and head components.


    Fuel doesnt come from the bottom of the tank. The inlet to the pump is always well above the bottom.
  • wolfe10 wrote:
    Suggest you change both fuel filters-- sucking fuel off the bottom of the tank will tend to clog filters.

    And, your manual primer pump made priming/starting a LOT easier.

    BTW, this is also hard on the whole fuel system, as fuel is used to cool and lube injection and head components.


    Yup, planning on changing both filters. The manual pump brought the pressure right up, just a slightly longer crank and the old CAT fired right up.
  • Suggest you change both fuel filters-- sucking fuel off the bottom of the tank will tend to clog filters.

    And, your manual primer pump made priming/starting a LOT easier.

    BTW, this is also hard on the whole fuel system, as fuel is used to cool and lube injection and head components.
  • I know that it doesn't really speak to you folks with those big ol' DP tanks, but the same theory applies.

    Same as with our 2 propane tanks, we have twin diesel tanks with a crossover. Our propane, we let one run out before the next trip to the store, but with our truck, if one gets down to 25%, it gets filled next available opportunity.

    As other have said, if you approach 45% gone in a single tank, get ye to a petrol place. You'll never sing the boo-hoo-hoo's.
  • My range on a full tank is far more than I will drive in a day. I try to fill up within an hour or less before I stop for the night when traveling. That way, I always start the day with a full or almost full tank and do not have to be concerned with refueling during the day.
  • I fill up at about 400 miles or half tank. Better safe than sorry.

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