Tractor loses power

fruitcakesa

Active member

Equipment
M 6040
Oct 26, 2010
777
178
43
Cavendish Vermont
Lately, when driving up slope, the engine will lose power to the point that in order to keep forward progress, I have to back off the throttle to maintain headway. As soon as it starts to level off, power returns.
Today, it also lost power on a downhill run and cleared up when back on the level.
I use freshly treated fuel with power service.
Any ideas
 

PaulR

Well-known member

Equipment
BX 23S -- 77.1 hours seat time so far
Aug 3, 2020
477
338
63
Hadley, MA
Try low range.
Does the trans feel like its slipping?
 

DevilDog

Member

Equipment
L3540 HST3, 72" Woods Rear Finishing Mower, L3584" Land Pride BB, 72" York Rake,
Feb 1, 2011
45
5
8
upstate N.Y.
Lately, when driving up slope, the engine will lose power to the point that in order to keep forward progress, I have to back off the throttle to maintain headway. As soon as it starts to level off, power returns.
Today, it also lost power on a downhill run and cleared up when back on the level.
I use freshly treated fuel with power service.
Any ideas
What range are driving in? Maybe you need to change into a medium range?
Devildog
 

kubotafreak

Active member

Equipment
GRAND l6060, L3560, B6100, gr2100, tg 1860, g1800, g1900, g2160
Sep 20, 2018
747
222
43
Arkansas, US
Fuel separator inlet should be checked. Air in the seperator bowl is a good indicator of a restriction in fuel delivery.
 
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Mark_BX25D

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Equipment
Bx25D
Jul 19, 2020
496
214
43
Virginia
It's a diesel. Loss of power is one of three things:


  1. Loss of compression.
  2. Loss of air supply.
  3. Loss of fuel supply.

Since yours comes and goes, it's not #1.
Since it's hard to imagine an obstruction in the air supply that would come and go with slopes, it's almost certainly not #2.

That leaves fuel. Hmmm. Liquids sloshing in a tank.... flow changing with slope.....

Yeah, that sounds like fuel.

I'd be looking at your fuel tank.
 
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JerryMT

Active member

Equipment
Kubota M4500, NH TD95D,Ford 4610
Jun 17, 2017
394
75
28
The Palouse - North Idaho
Lately, when driving up slope, the engine will lose power to the point that in order to keep forward progress, I have to back off the throttle to maintain headway. As soon as it starts to level off, power returns.
Today, it also lost power on a downhill run and cleared up when back on the level.
I use freshly treated fuel with power service.
Any ideas
Sounds like you may have restricted fuel delivery. Start at the line that delivers fuel to the injection pump (or the high pressure pump) and work back toward the tank. You should have gushing fuel flow through the lines at every point in the fuel circuit. When is the last time you changed the fuel filter? Are you in a cold climate where icing or fuel waxing might be an issue? DO you have winter fuel in the tank?
 

fruitcakesa

Active member

Equipment
M 6040
Oct 26, 2010
777
178
43
Cavendish Vermont
Sounds like you may have restricted fuel delivery. Start at the line that delivers fuel to the injection pump (or the high pressure pump) and work back toward the tank. You should have gushing fuel flow through the lines at every point in the fuel circuit. When is the last time you changed the fuel filter? Are you in a cold climate where icing or fuel waxing might be an issue? DO you have winter fuel in the tank?
It is cold here, and have yet to start checking specific items
I always use fresh fuel with power service in winter.
 

BAP

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Lifetime Member

Equipment
2012 Kubota 2920, 60MMM, FEL, BH65 48" Bush Hog, 60"Backblade, B2782B Snowblower
Dec 31, 2012
2,083
255
83
New Hampshire
Check your tank cap, could be not venting properly. With it as cold as it has been, the inside of the cap could be frosting over or the rubber that moves to allow air in may have become too stiff in the cold to move.
 
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fruitcakesa

Active member

Equipment
M 6040
Oct 26, 2010
777
178
43
Cavendish Vermont
OK, so I changed out the fuel filter and cleaned the fuel strainer
Pumped up the filter till it was hard to push the pump, filled the fuel strainer and then started it.
It ran for a minute, then began to stumble. I was able to keep it running and started to drive it back to the shed when it stumbled again and then quit.
I have not been able to restart it since.
It will crank fine but no start.
I opened the fuel cap in case that was the issue but no go.
I am stumped [being relatively diesel ignorant].
This is a real problem with a winter storm on the horizon.
Any help is greatly appreciated
 

JerryMT

Active member

Equipment
Kubota M4500, NH TD95D,Ford 4610
Jun 17, 2017
394
75
28
The Palouse - North Idaho
OK, so I changed out the fuel filter and cleaned the fuel strainer
Pumped up the filter till it was hard to push the pump, filled the fuel strainer and then started it.
It ran for a minute, then began to stumble. I was able to keep it running and started to drive it back to the shed when it stumbled again and then quit.
I have not been able to restart it since.
It will crank fine but no start.
I opened the fuel cap in case that was the issue but no go.
I am stumped [being relatively diesel ignorant].
This is a real problem with a winter storm on the horizon.
Any help is greatly appreciated
Did you check the fuel supply circuit from the main injector pump back to the tank? There are lots of places for fuel restrictions like the filter head (which supplies fuel to the filter), fuel lines, etc. That's why checking at the injector pump inlet is the place to start. If you don't have gushing fuel at that point you clearly have restricted fuel delivery. If you do have gushing fuel, then your problem is elsewhere.

Is there anything in the fuel supply circuit that could have a filter like a lift pump may have an internal screen? What about lines and fittings where clogs can occur. Do you have a separate water separator? Check that if you do.

Do you have a fuel shut off solenoid? Does it stay open when you get the engine started? They generally have two solenoids one for opening the fuel valve and one for holding it open long term.

If you're going to get this running before the storm you need to do some good diagnostics to locate the root cause of the problem. No short cuts. None of us can help you at a distance except by offering advice!

Good Luck!
 

North Idaho Wolfman

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Staff member
Lifetime Member

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
22,959
1,085
113
Sandpoint, ID
I'm a little lost?
If this on your M6040?
I don't see a hand pump on the fuel system?
With so many variations anything is possible.
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
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Sandpoint, ID
I'm a little lost?
If this on your M6040?
I don't see a hand pump on the fuel system?
With so many variations anything is possible.
Ok had to dig deeper found the pump.

To get it to the shop, bottle feed the injection pump.
Turn off the fuel at the separator / strainer,
Pull the fuel line off at the side of the injection pump ( the one that comes from the fuel filter) and attach a line to a bottle suspended above the injection pump.
This will get it running and into the shop or place to work on it.
Then when you have it there.
Connect a short hose off of the fuel filter into a container, start it, open the fuel cock at the strainer.
what you should be getting is a constant pulse of fuel, if you not shut it off and check for fuel flow at every point starting at the fuel filter working back.
If you have fuel flow, you have a bad / clogged/ damaged fuel lift pump.
If you don't have a good flow you have a clog, go to the last point of flow and the part before it is clogged.
 
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fruitcakesa

Active member

Equipment
M 6040
Oct 26, 2010
777
178
43
Cavendish Vermont
Ok had to dig deeper found the pump.

To get it to the shop, bottle feed the injection pump.
Turn off the fuel at the separator / strainer,
Pull the fuel line off at the side of the injection pump ( the one that comes from the fuel filter) and attach a line to a bottle suspended above the injection pump.
This will get it running and into the shop or place to work on it.
Then when you have it there.
Connect a short hose off of the fuel filter into a container, start it, open the fuel cock at the strainer.
what you should be getting is a constant pulse of fuel, if you not shut it off and check for fuel flow at every point starting at the fuel filter working back.
If you have fuel flow, you have a bad / clogged/ damaged fuel lift pump.
If you don't have a good flow you have a clog, go to the last point of flow and the part before it is clogged.
Wolf, thanks for the specific info on getting it going.
I am hoping it is just a clog or trapped air and not something electrical or other.
We are looking at potential major snow, high winds and deep freeze tomorrow.
We'll see how it goes.
 

fruitcakesa

Active member

Equipment
M 6040
Oct 26, 2010
777
178
43
Cavendish Vermont
Did you check the fuel supply circuit from the main injector pump back to the tank? There are lots of places for fuel restrictions like the filter head (which supplies fuel to the filter), fuel lines, etc. That's why checking at the injector pump inlet is the place to start. If you don't have gushing fuel at that point you clearly have restricted fuel delivery. If you do have gushing fuel, then your problem is elsewhere.

Is there anything in the fuel supply circuit that could have a filter like a lift pump may have an internal screen? What about lines and fittings where clogs can occur. Do you have a separate water separator? Check that if you do.

Do you have a fuel shut off solenoid? Does it stay open when you get the engine started? They generally have two solenoids one for opening the fuel valve and one for holding it open long term.

If you're going to get this running before the storm you need to do some good diagnostics to locate the root cause of the problem. No short cuts. None of us can help you at a distance except by offering advice!

Good Luck!
Thanks for the advice. I have some digging to do.
 

RCW

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Equipment
BX2360, FEL, MMM, BX2750D snowblower. 1953 Minneapolis Moline ZAU
Apr 28, 2013
6,420
1,677
113
Chenango County, NY
fruitcake - - - I don't to profess to have any specific knowledge....just trying to help.

Many times guys have found crap in the inlet fittings going into the separator housing. Not evident in the separator itself, as it's before the housing the separator screws into.

Recall it to be a 90 degree fitting going into the top housing?

It's hay pieces/crap plugging the fitting(s) into the housing.

@kubotafreak mentioned it earlier.

Recall it more commonly with some of the "L" series, but maybe same for an "M" as well??

Again - - may be way off, but thought I'd mention it......

In all sincerity, best wishes.....
 
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Thunder chicken

Active member

Equipment
M7060
Dec 29, 2019
218
74
28
Northern ontario
^ good advice. This is what a dealer recommended me to check a while ago…..
I found dirt in fuel tank (a piece of foil from the power service bottle cap!) blocking the suction line… occasionally…..
 
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