M7060 bogging down.

[BufordBoone]

I'm experiencing a bit of an M7060 (2018 model) Issue when bush hogging.

I Set PTO speed to 540. Once I begin cutting it will usually drop to about 525-530. Fluctuates mildly while cutting, depending on up or down hill, etc.

Will run well for about 1.5 - 1.75 hours. Then it will begin to bog down. Changing to lower gear will bring PTO speed back up. Then it will bog again. Eventually, It will have to be in 2nd or 1st gear to keep PTO speed up, even in sparse grass.

Once it gets in this state, engaging one of the rear hydraulics (lift rear or wings of mower) will also bog the engine down dramatically.

When first starting up today, I verified that engaging one of the rear hydraulics does not bog engine down while functioning normally.

It has done this with both a 12’ wing mower and the 10’ offset mower. I hooked the wing mower to our L5740 and it cut the same area without difficulty.

Both tractors use fuel from the same transfer tank.

It has been doing this for about a week. I park it overnight and it seems to be fine the next day, for 90 minutes or so. Then, same symptoms.

Things I’ve tried:

Throughly cleaned all radiators
Changed both inner and outer air filter.
Drained the water separator.
Verified sufficient hydraulic fluid.

A friend has a neighbor that used to be a tractor mechanic. He explained the symptoms to the neighbor who said "It sounds like a sensor that may have gone bad. Whatever it is is something trying to protect the system".

Has anyone out there experienced anything similar? Any ideas before I have it taken in to the dealer?

Thanks.

 

[pjbci]

Change fuel filters.

 

[BufordBoone]

Change fuel filters.

Good idea. I thought about that but didn't have a spare. I'll get one tomorrow. Thanks for the recommendation.

If the fuel filter is causing the issue, how/why would it operate normally for the first 90 minutes? Also, what would that have to do with the hydraulics bogging the engine down?

 

[5030]

Lack of sufficient fuel will 'bog' everything down as the engine is powering EVERYTHING.

 

[pjbci]

Good idea. I thought about that but didn't have a spare. I'll get one tomorrow. Thanks for the recommendation.

If the fuel filter is causing the issue, how/why would it operate normally for the first 90 minutes? Also, what would that have to do with the hydraulics bogging the engine down?

All I can tell you for a reason about the 90 minutes is that sometimes they act like that, sometimes they’ll cause even stranger issues. 50 years of making groceries with machines has taught me when you lose power, change fuel filters first, then persue other issue if that does not correct the problem.

The hydraulics place load on the engine too. If engine is already starved for fuel, the slight increase in load from hyd pump will bog it down as well.

 

[5030]

That is a common rail T4 engine so I suspect there are other issues as well. You really need your dealer to make a farm call and use the Diagmaster scan tool on it to determine EXACTLY what the issue is.

 

[JWR]

I doubt the origin of this symptom has anything to do with the tractor itself. You probably did not run the mowers long enough on the 5740 to experience it.

My thought is that the mower is getting hot and binding. Taking more HP to run it. Might be twine or other debris wound around spindles that gets hot from friction and expands or begins to bind worse. Hopefully NOT the mower gear boxes which you no doubt check for lube level, etc.

The problem with my theory is that hydraulics bogs down the engine... OOPS ! Is this a turbocharged engine?

 

[RickB]

Change the fuel filter and clean the water separator if so equipped. If your symptoms persist call your dealer and tell him you think your injectors are faulty. There is a PSB that is specific to your problem. You might want to check that the mower turns as freely when the tractor power seems compromised as when you first start it up by disconnecting the PTO and turning the shaft by hand.

 

[Jerry/MT]

I'm experiencing a bit of an M7060 (2018 model) Issue when bush hogging.

I Set PTO speed to 540. Once I begin cutting it will usually drop to about 525-530. Fluctuates mildly while cutting, depending on up or down hill, etc.

Will run well for about 1.5 - 1.75 hours. Then it will begin to bog down. Changing to lower gear will bring PTO speed back up. Then it will bog again. Eventually, It will have to be in 2nd or 1st gear to keep PTO speed up, even in sparse grass.

Once it gets in this state, engaging one of the rear hydraulics (lift rear or wings of mower) will also bog the engine down dramatically.

When first starting up today, I verified that engaging one of the rear hydraulics does not bog engine down while functioning normally.

It has done this with both a 12’ wing mower and the 10’ offset mower. I hooked the wing mower to our L5740 and it cut the same area without difficulty.

Both tractors use fuel from the same transfer tank.

It has been doing this for about a week. I park it overnight and it seems to be fine the next day, for 90 minutes or so. Then, same symptoms.

Things I’ve tried:

Throughly cleaned all radiators
Changed both inner and outer air filter.
Drained the water separator.
Verified sufficient hydraulic fluid.

A friend has a neighbor that used to be a tractor mechanic. He explained the symptoms to the neighbor who said "It sounds like a sensor that may have gone bad. Whatever it is is something trying to protect the system".

Has anyone out there experienced anything similar? Any ideas before I have it taken in to the dealer?

Thanks.

Make sure you have adequate fuel delivery to the injection pump (IP). Start at the tank outlet then at the tank outlet hose to the fuel filter, then at the fuel filter outlet and then at the IP inlet. Look for a clogged screen at the IP inlet. If you have a lift pump in the circuit, check at the inlet and out let of the lift pump (some lift pumps have a removable cap over an internal screen.). At every location you should have a gush of fuel like a cow peein' on a flat rock! Make sure the tank vent is clear. It maybe in the fuel cap or maybe separate. If you do have the requisite fuel delivery, check the fuel return to tank line for plugging. Make sure all the connections in the fuel delivery system are tight and not sucking air.
If you pass the fuel delivery test, it's either some sensor if you have Tier IV engine or the IP though the latter is a last resort thing after everything else has been eliminated

 

[BufordBoone]

I doubt the origin of this symptom has anything to do with the tractor itself. You probably did not run the mowers long enough on the 5740 to experience it.

I ran the mower on the 5740 for about 3.5 hours, no issues.

All good replies and much appreciated.

 

[BufordBoone]

Additional. The engine runs fine and doesn't seem "starved" for fuel, except when I put a load on it. In other words, when the issue happens, simply disengaging the PTO and it the engine doesn't bog down. Then, pulling on one of the hydraulic remotes bogs it down.

Strange but, thanks, again, for all the advice.

 

[5030]

Time to trundle down to HF and buy a 35 dollar non contact IR thermometer.

 

[Jerry/MT]

Additional. The engine runs fine and doesn't seem "starved" for fuel, except when I put a load on it. In other words, when the issue happens, simply disengaging the PTO and it the engine doesn't bog down. Then, pulling on one of the hydraulic remotes bogs it down.

Strange but, thanks, again, for all the advice.

You do realize that when you run the engine without load and it runs fine, you are using a minimum amount of fuel. When you add load, the fuel flow has to increase to hold almost constant rpm with load. So your fuel delivery system may be able to deliver enough fuel at no load idle but cannot provide enough fuel to the injector pump to run under load.

 

[BufordBoone]

You do realize that when you run the engine without load and it runs fine, you are using a minimum amount of fuel. When you add load, the fuel flow has to increase to hold almost constant rpm with load. So your fuel delivery system may be able to deliver enough fuel at no load idle but cannot provide enough fuel to the injector pump to run under load.

Well, NOW I do realize that. Should have been obvious. Thanks.

 

[Like Tractors]

I'm experiencing a bit of an M7060 (2018 model) Issue when bush hogging.

I Set PTO speed to 540. Once I begin cutting it will usually drop to about 525-530. Fluctuates mildly while cutting, depending on up or down hill, etc.

Will run well for about 1.5 - 1.75 hours. Then it will begin to bog down. Changing to lower gear will bring PTO speed back up. Then it will bog again. Eventually, It will have to be in 2nd or 1st gear to keep PTO speed up, even in sparse grass.

Once it gets in this state, engaging one of the rear hydraulics (lift rear or wings of mower) will also bog the engine down dramatically.

When first starting up today, I verified that engaging one of the rear hydraulics does not bog engine down while functioning normally.

It has done this with both a 12’ wing mower and the 10’ offset mower. I hooked the wing mower to our L5740 and it cut the same area without difficulty.

Both tractors use fuel from the same transfer tank.

It has been doing this for about a week. I park it overnight and it seems to be fine the next day, for 90 minutes or so. Then, same symptoms.

Things I’ve tried:

Throughly cleaned all radiators
Changed both inner and outer air filter.
Drained the water separator.
Verified sufficient hydraulic fluid.

A friend has a neighbor that used to be a tractor mechanic. He explained the symptoms to the neighbor who said "It sounds like a sensor that may have gone bad. Whatever it is is something trying to protect the system".

Has anyone out there experienced anything similar? Any ideas before I have it taken in to the dealer?

Thanks.

I have been through a low power problem with an M7060 after 1-2 hours of use that required most of the engine horse power. I suggest you measure fuel pressure at the fuel filter inlet while running under load. As long as you have proven that you don't have a fuel restriction before the electric fuel pump, you have a serious problem on your hands. Contact me for details.

 

[RickB]

I’m gonna refer you back to post #8. Read it again. I see you have run the cutter with a different tractor to eliminate it as your cause .

 

[Hay Dude]

Fuel filters.
A month ago I was baling a field an noticed when the plunger was about to hit (big power drain), my MX270 would bog down. It idled and ran normally with no load. Knew it was FF’s. Changed primary and secondary fuel filters. After a few minutes of air getting bled, it ran like a champ.
Just remember after you change them it could take a few minutes to run smooth again.
If that doesn’t do it, listen to RickB. I agree with his thoughts and he knows what he’s talking about.

 

[tmajor]

I'm experiencing a bit of an M7060 (2018 model) Issue when bush hogging.

I Set PTO speed to 540. Once I begin cutting it will usually drop to about 525-530. Fluctuates mildly while cutting, depending on up or down hill, etc.

Will run well for about 1.5 - 1.75 hours. Then it will begin to bog down. Changing to lower gear will bring PTO speed back up. Then it will bog again. Eventually, It will have to be in 2nd or 1st gear to keep PTO speed up, even in sparse grass.

Once it gets in this state, engaging one of the rear hydraulics (lift rear or wings of mower) will also bog the engine down dramatically.

When first starting up today, I verified that engaging one of the rear hydraulics does not bog engine down while functioning normally.

It has done this with both a 12’ wing mower and the 10’ offset mower. I hooked the wing mower to our L5740 and it cut the same area without difficulty.

Both tractors use fuel from the same transfer tank.

It has been doing this for about a week. I park it overnight and it seems to be fine the next day, for 90 minutes or so. Then, same symptoms.

Things I’ve tried:

Throughly cleaned all radiators
Changed both inner and outer air filter.
Drained the water separator.
Verified sufficient hydraulic fluid.

A friend has a neighbor that used to be a tractor mechanic. He explained the symptoms to the neighbor who said "It sounds like a sensor that may have gone bad. Whatever it is is something trying to protect the system".

Has anyone out there experienced anything similar? Any ideas before I have it taken in to the dealer?

Thanks.

Just had a similar sounding problem. ... New fuel filter cured it.

 

[IFixTractors]

Number one issue with this is always new fuel filter and clean/check the water separator. Second, Kubota has a bulletin for replacement fuel injectors for the V3307 engines in a certain engine serial number range. This is considered a warranty and emissions part, so they have some extension to the base warranty on this particular part. Please make contact with your local dealer to see if your machine is affected by this bulletin.
The V3307 engine is used in several different Kubota machines. M6060 and M7060, SVL75-2, M4, and KX080-4, among others.

 

[IFixTractors]

PSB-2021-007-E-R1​

Is the bulletin number.

Issue:
There is a possibility that engine power may drop at operating temperature. The nozzle body may not open/close due to an internal failure of the injector. (Other than contamination in fuel)

This is covered for 5 years from date of original purchase, no hour limit.

Many people have complained about low power issues, and now it is a known issue. Had one customer that went so far that he bought another brand because the power was low, never got the Kubota service reps involved (dealer didn't help), just complained about the issue. The rep took a 5 min look at it, yep, bad injectors, and had the dealer install new. Power is fine, customer was now upset at the dealer (of course) and at himself for buying another machine. He liked his Kubota other than that low power issue.

Hope this helps.