MX5100DT fuel valve info

SRRGC1

Active member

Equipment
BX1870-1, BX23S TLB, RTV XG850, MX5100DT
Jan 6, 2021
208
75
28
Bloomsburg
Have a MX5100DT. In the process of changing the fuel filter, I rotated the petcock to the "off" position as as the arrow indicated and as I have done in the pass. Upon removing the large nut and bowl, some fuel continued to run. I immediately checked position of the petcock to make sure it was in the "off" position and it was. I proceeded to change the filter with fuel still running slightly. I rotated the petcock to the "on" position and as expected, fuel flowed more. Closed the petcock again and completed installing the new fuel filter. "Off" position is up with "on's" on both sides. I have changed this filter in the past with no fuel leaking pass the petcock valve. Also the fuel valve has two "on' positions and one "off" position. My owners manual does NOT indicate this only the "on" and "off" petcock positions. Could this fuel valve be designed with a "reserve" fuel position kind of like a motorcycle/atv? OM does not indicate this. Once the filter was replaced and nut installed everything find with tractor. I believe the petcock is just a "barrel" type valve. Also, and as expected, when I turned the fuel valve back "off" with the tractor running, engine continue to run indicating fuel was still passing through the fuel valve when "off". Tractor runs fine and doesn't miss a beat at fuel throttle. Has anybody else experienced this issue or suggest a possible problem. Tks.
 

freewheel3

Active member

Equipment
MX5000DT LA852, BX1800D, B6000DT, B6200HSTD, B7100HSTD, L185, T1700HX, ZD1211
Mar 9, 2013
334
33
28
Alberta
Sounds to me like you have a leaky petcock. There is an o-ring seal and packing inside it, One of them might be damaged or have debris in it. Its probably got something to do with #s 040 or 070 in the attached link. Click the accept terms button.
 

Motion

Well-known member
Lifetime Member

Equipment
Kubota MX5100HST/FEL
Aug 17, 2020
524
289
63
Mandeville Louisiana
I believe the down position is not what you think fully clockwise is off, fully counterclockwise is on, facing the valve.
 

SRRGC1

Active member

Equipment
BX1870-1, BX23S TLB, RTV XG850, MX5100DT
Jan 6, 2021
208
75
28
Bloomsburg
Be reminded that there's a spring that goes under the filter.
Yep, filter was installed correctly, no issues there. Just was unable to completely stop the flow of diesel when changing filter. Did slow it down to a trickle, but did not stop it. Tractor is filled with a FEL, so very difficult to get at filter. Is what it is.
 

SRRGC1

Active member

Equipment
BX1870-1, BX23S TLB, RTV XG850, MX5100DT
Jan 6, 2021
208
75
28
Bloomsburg
Sounds to me like you have a leaky petcock. There is an o-ring seal and packing inside it, One of them might be damaged or have debris in it. Its probably got something to do with #s 040 or 070 in the attached link. Click the accept terms button.
Not going to worry about it alot. Have had the tractor for nearly 9 years and only have 227 hrs. on it. Used at a hunting camp in NEPA for food plot work and clearing log roads. Only the second filter change and probably didn't even need that. What you said is just what I suspected. I thought by opening up the petcock with the filter off might dislodge any debris. Tks.