JD X748 Sucking Fuel Like Candy

[eagle107]

Guys,

My uncle and I both received our new JD X748 w/7 iron 60" decks back in March of this year. I now have 16 hours on my X748 and he has 25 hours on his X748. We both commented that these little tractors seem to suck diesel fuel like candy taking about 3 1/2 gallons of diesel fuel to cut 2 acres around our houses. While my 4520 can cut almost three times as much grass (in ePTO mode) using the same amount of fuel as the X748 and my Uncle's 3520 can cut twice as much grass using the same amount of fuel as his X748. Now I realize the X748 is cutting at 3200rpms versus 2400rpm on the 3520 and 1750rpms on the 4520. Also, the Scag Tiger Cat w/a 52" deck I had previous could cut the same amount of grass (2 acres) with 3 1/2 gallons of gas, so it seems the JD X748 is not that much better on fuel consumption as the Scag. My uncle and I are thinking of cutting our grass at half throttle to see if the fuel consumption will go down. Has anyone else seen this issue with the X748? Is this the right amount of fuel consumption for a tractor this small with the AWD? Is there something wrong with these tractors? Thanks in advance for the help.

 

[arlen4720]

I have been cutting 5 or 6 acres with my x748 for the past 7 years. It takes about 5 gal of fuel to do it, so your fuel consumption is greater than mine. I have the older x748 without the full time 4wd, and I would guess that is a factor. Also, I have the 62C deck. I suppose it matters how thick your grass is compared to mine. I can tell you that when I blow heavy snow, it really sucks fuel, but the engine is really working. I always mow at PTO speed. I have never considered my x748 a fuel hog.

 

[jenkinsph]

Mowing my lawn area runs about 1 gallon/acre with a 48" deck, would problably be a little less with a larger deck (on my x749). This takes about an hour and a half to mow, cost about $10 bucks with fuel and beverages. Quality time and saves on bills for a shrink.

 

[eagle107]

Well my grass can be heavy at times, but the Scag just cut right through it like it was nothing at full speed; the Scag only had a Kohler Command 25. I am starting to wonder if the Velocity Plus deck on the Scag is superior to the JD 7 Iron deck when cutting. When I cut at full speed with the X748, I can actually see the fuel gauge moving. I did get a little mad the other day when cleaning off the 7 Iron deck and saw the spindles were made in China while the Scag was fully made in the USA. It is pretty frustrating to see a diesel machine use as much fuel as a gas machine. The only thing the X748 provides is not getting stuck in the wet spots like I did with the Scag; that was a major pain. Below is what we cut with the X748.

 

[jenkinsph]

Guys,

My uncle and I both received our new JD X748 w/7 iron 60" decks back in March of this year. I now have 16 hours on my X748 and he has 25 hours on his X748. this the right amount of fuel consumption for a tractor this small with the AWD? Is there something wrong with these tractors? Thanks in advance for the help.

Didn't pay much attention to this initially but with hours that low I would expect a little extra fuel burn. Your fuel usage should get better with a few more hours on the clock.

 

[Turbys_1700]

I would expect your fuel usage to go down as the engine breaks in...
Just as a reference, my New Holland 1720 with a 28 HP Shibaura and 6' Woods RFM will go through approximately 1 gal per hour while mowing my lawn and other areas...
I am currently mowing around 3-1/2 acres give or take in around 2 hours...
That is a very low acreage per hour but I have hilly ground and mow in areas that are not considered lawn...
My typical travel speed is in the 3.5 MPH range but I have lots of stops and starts...
I personally don't think that your fuel usage is out of the norm considering that you are turning 3200 rpms...
I am burning around 1 gal per hour at 2500 rpm's...
Pretty comparable...

 

[KennedyDiesel]

Forget the acre factor and start tracking gallons to hours. I think as it has been said it may take a bit to break in and the MPG go up. Time will tell. It seems that the fuel gauge is plenty active on the x750 vs my 455 as well. Smaller tank plus it's Ma's machine so I'm not running it most of the time.

 

[oldnslo]

Does anyone have a guide to HP based on gallon per hour of fuel used.

In the late 60's early 70's rule of thumb was 16 HP/gal naturally aspirated 20 HP/gal with Turbo

My Branson 2400H with 60" MMM has to be worked pretty hard and steady to burn a gallon/hr

 

[ccsial]

I have been cutting 5 or 6 acres with my x748 for the past 7 years. It takes about 5 gal of fuel to do it, so your fuel consumption is greater than mine. I have the older x748 without the full time 4wd, and I would guess that is a factor. Also, I have the 62C deck. I suppose it matters how thick your grass is compared to mine. I can tell you that when I blow heavy snow, it really sucks fuel, but the engine is really working. I always mow at PTO speed. I have never considered my x748 a fuel hog.

I have the 54C deck on my 2007 X748 and I use about 2 gallons for just over 2 acres. Much less than the gas tractor I had some years ago.

My 2005 L3400 with the woods RD72 RFM uses about the same Gallons per acre though, so I guess it is more efficient.

The full time 4wd may be a factor since it is hydraulic which is not the most efficient method. I also wonder if the new EPA approved engines burn more fuel as in the pickups. I have a 97 Dodoge Cummins (mechanical injection) with 70,000 miles I plan to keep forever. If I had to buy a new truck I wouldn't go with diesel today.

 

[JDTank]

I have a 2012 X740 with the 54 inch deck, and my numbers are MUCH lower than yours. However, I think I can see a few reasons why.

The X748, as someone already pointed out, has a hydro AWD system. Your AWD machine has a 6 GPM charge pump. My machine being a 2WD, has a 4.5 GPM charge pump. So, your front wheels must constantly be fed power via the hydro system. The charge pump is considerably larger, specifically to handle the extra GPM needed on a hydro driven axle like the front one on your X748.

My deck is a 54 inch. While minor, bigger blades take more effort to turn, and catch more wind when turning, requiring more effort yet to keep speed. Your deck is a 60 inch correct? If you have the 7-Iron deck, that deck weighs something like 330 pounds. My 54C deck weighs 150 pounds. You are carrying 180 pounds more weight around your yard all day long than I am. Considering the weight of these machines, it probably works out to about a 15% increase overall, which is big.

I cut about 1.5 acres around the house area, and I would say I use probably a gallon of fuel. I keep my speed fairly low to maintain cut quality, and I think that helps save fuel as well. When your mower deck is engaged, it robs a large portion of power from your hydro system. If you try to cut with a high ground speed, I wouldn't be surprised if your fuel economy is worse because of it.

So overall, your machine is working harder to move more weight, with a hydro driven AWD system, pumping more hydro fluid, and turning bigger blades, it all adds up. Your consumption does seem a little high to me, even after all that. Although, if your machine is new, it will take some time to break in a diesel. I have 30 hours on my 2012 diesel now, and I am guessing it will take at least 300 before it is broken in and running as efficient as possible.