Engine acts fuel starved? Starts up well. Goes 3-8 minutes. Good RPM/power/no smoking. Then, we lose power/drop in RPM/not very throttle sensitive. Engine may die. If not, the anemic performance continues. Acts like we need to put the patient on life support. After cool down, restarts well to repeat the process. Radiator fluid looks ok and no gross bubbling. Engine oil looks fine, not milky and viscosity seems ok. Temperature gauge ok. Fuel filter changed, water separator cleaned, lines bled, Howes diesel fuel additive added. Thought we might be over the hump. Problems resumed shortly thereafter. Stymied. Blockage in lines/tank? Other ideas. And if so, how to diagnose and treat please.Thanks for your thoughts.
Erratic power problem: M6800DT
- Thread starter farmer98
- Start date
RCW
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Equipment
BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
Some guys here have had a piece of trash will float around the tank outlet, and after a bit of running, get drawn to the tank outlet, starving the engine.
For most I recall on here, it does take some running time before the trash blocks the outlet.
Try pulling fuel line off to gauge flow off tank, see if running good without interruption after couple gallons run off.
Just a thought, and best of luck finding the culprit.
For most I recall on here, it does take some running time before the trash blocks the outlet.
Try pulling fuel line off to gauge flow off tank, see if running good without interruption after couple gallons run off.
Just a thought, and best of luck finding the culprit.
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85Hokie
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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
I second the trash in the tank.......something could be floating around and hitting the right spot then moving away - why is takes a while to get there, not sure. Drain fuel and bleed lines, report back
Does your fuel gauge work like it should or if you fill the tank does it fill the left tank but it still shows only partially full and you gauge?
If so sounds like you vent tubes are stopped up. It should have a tube on both sides of the tractor right in front of the cab or platform whichever you have.
If so sounds like you vent tubes are stopped up. It should have a tube on both sides of the tractor right in front of the cab or platform whichever you have.
rbargeron
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L5450, L48, L3250, L345 never enough attachments
The M6800 has 2 low-mounted tanks so it has several tubes and fittings in the fuel/vent system. The attached pdf's from the Kub website are for the rops version - the cab versions show even more twists and turns.
The transfer pump has to lift the fuel up to the injection pump so there are several places where an air leak could interfere with the fuel supply. It might run ok for a while before air in-leakage started affecting it. A small check valve #240 is shown near the fuel filter/separator. Not sure about its function, maybe it's not holding?
FWIW my L5450 had a similar fuel starvation problem years ago that was caused by a combination of debris in the tank and a too-effective factory vent line that defeated even a tiny amount of pump suction. I tried pinching off the extra vent line leaving only the tank cap to do the venting. It did the trick and has worked fine ever since.
The transfer pump has to lift the fuel up to the injection pump so there are several places where an air leak could interfere with the fuel supply. It might run ok for a while before air in-leakage started affecting it. A small check valve #240 is shown near the fuel filter/separator. Not sure about its function, maybe it's not holding?
FWIW my L5450 had a similar fuel starvation problem years ago that was caused by a combination of debris in the tank and a too-effective factory vent line that defeated even a tiny amount of pump suction. I tried pinching off the extra vent line leaving only the tank cap to do the venting. It did the trick and has worked fine ever since.
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