Oil & Fuel 3x20 Cab fuel guage.

[nmu98]

I have a whopping 5 hours of rotary cutting on my 3720. On my open station, i would be at half tank. That thing loved diesel.... I have yet to see the fuel guage move off full on the new tractor. I opened the fill and i can see its using fuel! but no guage movement. Does the tank under the wheel well stay full on the guage then go empty fast? I don't want to runn out of fuel to find out the guage is not working.

 

[JasonMac]

I find that on my 3720 Cab tractor, the fuel gauge doesn't move from full for quite a long time, but once it hits 3/4 mark the gauge can move down quite a bit faster. It must have something to do with the geometry of the linkage. So keep an eye on it once you hit 3/4 of a tank, because before you know it, it will be closer to 1/4 tank....

 

[jsboening]

Mines the same way.

 

[kiwiroo]

I notice too that when my gauge is pretty much on empty if I put in 5 gallons it goes almost back up to full which can't be right since it is 11 gallon tank on the cab-

 

[nmu98]

I notice too that when my gauge is pretty much on empty if I put in 5 gallons it goes almost back up to full which can't be right since it is 11 gallon tank on the cab-

My Open Station was the same way, and I believe they have a 13 gallon tank?

Glad to hear I most likely do not have a bad guage.

 

[sunnyside360]

I find that on my 3720 Cab tractor, the fuel gauge doesn't move from full for quite a long time, but once it hits 3/4 mark the gauge can move down quite a bit faster. It must have something to do with the geometry of the linkage. So keep an eye on it once you hit 3/4 of a tank, because before you know it, it will be closer to 1/4 tank....

Same on my 3720 cab tractor. At first I thought the gauge was messed up.
Mine also does very good on fuel. I've been keeping track for about one year and it's averaging 0.6 gal per hour mowing 6 acres of lawn with 72" 7-Iron mower at about 2200 rpm.

 

[Nuru]

Well, mine stayed at full for a few days, then gradually moved down to 3/4 tank, then to 1/2, it did not accelerate, but I will check how much fuel i need to put in it at the next partial fill-up.

 

[nmu98]

I finally came off full this morning.

 

[Nuru]

Well, mine stayed at full for a few days, then gradually moved down to 3/4 tank, then to 1/2, it did not accelerate, but I will check how much fuel i need to put in it at the next partial fill-up.

break, break, Comm check, break, break, uddenly down to 1/4 tank, missed the 1/2 to 1/4 transition as it seemed to havwe done it between start-ups LOL! i will watch more closely next time.

 

[Karl2]

Same here, gauge seemed stuck on full for a few days then sudden drop to half mark then, seemingly overnight while tractor not in use, drops to 1/4. Now I see why the manual states "Shows approximately how much fuel is in the fuel tank."

I only used the tractor for 2 hours at moderate throttle since last fill-up so I know there's more fuel in there than the gauge says (no leaks) but just how much is anyone's guess. I suspect the extreme cold temps we've been experiencing the last few days may have an effect on the gauge.

 

[WH401]

When I was mowing with mine for the first time in late summer, the guage would move to between 3/4 and half after 2hrs at pto speed from a full tank. Then after another 2 hrs at pto speed, it would go to 1/4. When the guage shows 1/4 i still have 9.5 gallons left in the tank. Also the guage never really shows full, the highest it goes is 7/8 even if I fill the tank to just below the neck. No big deal though, I have never had a tractor that either had a fuel guage or one that functioned properly, so I just based it on hourly calculations.

 

[Nuru]

When I was mowing with mine for the first time in late summer, the guage would move to between 3/4 and half after 2hrs at pto speed from a full tank. Then after another 2 hrs at pto speed, it would go to 1/4. When the guage shows 1/4 i still have 9.5 gallons left in the tank. Also the guage never really shows full, the highest it goes is 7/8 even if I fill the tank to just below the neck. No big deal though, I have never had a tractor that either had a fuel guage or one that functioned properly, so I just based it on hourly calculations.

Last weekend I ran for about 6 hours (left it running over lunch too - forgot it was on it was so quiet! ), and the tank slowly dropped down to 1/3 a tank from almost full (I think - it could have been less). So next time I fill it up, I will watch it more closely.

 

[Karl2]

Well, now I know for sure my fuel gauge cannot be trusted, at least not when it's cold. Worked for a few hours blowing snow and gauge remained between 1/2 and 1/4 then poof, engine just stops with gauge still at 1/4. Initially I didn't even suspect the tank was empty and spent a few tedious hours troubleshooting my dead machine, then figured I'd drain the remaining fuel and check filters, but not before first adding new fuel and see what happens.

Went to purchase 10 gallons of fresh diesel and some stuff that prevents fuel gelling. At first I poured only about a gallon and went to check if the gauge had reacted and guess what, it was now reading a full tank! wtf? Gave up on gauge accuracy and poured the whole 10 gallons in the tank with room to spare, dang thing was as dry as Death Valley. Turned the key and it started right up and ran great for a whole 15 seconds or so, then died. Took me another few hours and searching this forum to realize I had neglected to use the hand primer. Doh! Of course by then I had completely drained the battery so I had to boost it with my old pickup. Took a lot of priming but got it running at last, been running smoothly for 30 minutes now, I'm letting the battery charge.

Moral of the story: don't trust fuel gauge and if you run dry, prime!

Now gotta get up at 4am to finish job I was supposed to do tonight, sigh!

 

[zr2blz]

My gauge is working great. When it hits 1/2 full I put in a 5 gallon can. I'm getting about 3 hours per gallon. Don't run high RPMs doing loader / backhoe work. I have 400 hours on her and it's one year old.

 

[Ramairfreak98ss]

i only have 7hrs on my 4720, hardly have run any rpms into it, like 1500 or less so it hasnt really been worked yet, just driving around a little, idling, messing with attachments etc.

its still on F, for a 13.8 gallon tank for the cab. I hope this thing can run around 1gallon per hour with pushing snow, that would net me all day plowing time for one tank

Says in the specs it can eat up like 3gph through, id guess thats wide open with a heavy load with the turbo going full the whole time. Ive only heard the turbo faintly spool up one or two times now

 

[Ramairfreak98ss]

karl2, where is the hand primer? somewhere near the fuel water seperator? is that only when they run dry?

 

[Karl2]

karl2, where is the hand primer? somewhere near the fuel water seperator?

Yes, it's right on top of it.

is that only when they run dry?

I guess anytime you need to flush fuel lines you may have to prime but if you run run dry you must prime after refueling or it won't start.

Noticed another fuel oddity today, after running about 6 hours on high rpm on my 10 gallons I noticed the message "lo fuel" was displayed on the digital readout but the gauge was still reading full and I was in my own parking lot so I didn't pay attention to it... and ran dry again, this time with gauge still on full. I thought at least the computer tells me when I'm low on fuel but the same message appeared again about 90 minutes after I filled the tank. Thinking I may be dealing with a leak I looked in the tank but it was still almost full to the brim. I really think cold temps play tricks on the fuel gauging system on this tractor. Not a big deal I guess.

 

[Nuru]

You might want to ask a local dealer about that issue and see if they have technical service bulletin on that problem.

 

[Karl2]

You might want to ask a local dealer about that issue and see if they have technical service bulletin on that problem.

Good idea

 

[Nuru]

Yeah, I actually ask here and use that as background info when I go into the dealer on the hard issues.