M7060 bogging down.

[whitetiger]

Have you actually tested an M7060 under load while measuring fuel supply pressure to the fuel filter, fuel rail pressure and horsepower? I will save you the time, while fuel supply pressure to the inlet side of the fuel filter is at -2 PSI, rail pressure remains within the range to not set codes and the tractor seems to run normally except power is somewhat lower. Now, while the fuel supply pressure is that low and the fuel temperature gets higher you get fluid dynamic cavitation, continued use under that condition destroys high pressure fuel system components. Eventually a misfire and substantial reduction in power output. But, no codes are set!

So, you are trying to convince people that the fuel rail pressure is in the normal range with a vacuum (-2 PSI) on the inlet side of the fuel filter???
You are making a fool of yourself.
The guy got his tractor fixed by a competent Tech, the fuel injectors were failing just as Kubota and Bosch, the manufacturer of the injecters have discovered. Bosch has discovered that the injectors supplied to Kubota for certain engines wear out rapidly. They will replace them under warranty for 5 years.

 

[Like Tractors]

So, you are trying to convince people that the fuel rail pressure is in the normal range with a vacuum (-2 PSI) on the inlet side of the fuel filter???
You are making a fool of yourself.
The guy got his tractor fixed by a competent Tech, the fuel injectors were failing just as Kubota and Bosch, the manufacturer of the injecters have discovered. Bosch has discovered that the injectors supplied to Kubota for certain engines wear out rapidly. They will replace them under warranty for 5 years.

I am not trying to convince anyone of anything. I have the test data to prove my statement. You don't seem to believe it is possible for that to occur, have you ever tested a GM pickup with a Duramax diesel engine 2001 thru 2016. I dyno test diesel engines, that is how I know this. By the way the Kubota M7060 uses a Denso fuel system, not Bosch. Duramax diesels use a Bosch system 2001 thru 2016 with no fuel supply pump providing fuel to the fuel filter and high pressure pump, they run with a substantial negative pressure at the high pressure pump inlet when tested under load.

 

[BufordBoone]

I ran the tractor for a couple of hours yesterday. Used the PTO in economy mode. Ran normally and didn't bog down.

I believe it is back to normal.

Thanks, to all, for the advice.

 

[whitetiger]

I am not trying to convince anyone of anything. I have the test data to prove my statement. You don't seem to believe it is possible for that to occur, have you ever tested a GM pickup with a Duramax diesel engine 2001 thru 2016. I dyno test diesel engines, that is how I know this. By the way the Kubota M7060 uses a Denso fuel system, not Bosch. Duramax diesels use a Bosch system 2001 thru 2016 with no fuel supply pump providing fuel to the fuel filter and high pressure pump, they run with a substantial negative pressure at the high pressure pump inlet when tested under load.

Yes, the fuel system is labeled as Denso, I don't know why I typed Bosch, although Bosch owns a minor percent of Denso.
No, I have never tested a Duramax under load, but I have tested at least 50 SVLs and L, Grand L, and M series Kubota units.

 

[BufordBoone]

I cut a bunch of thick grass this weekend. Tractor is working normally. Thanks, again, to all for the advice.

Thankful, also, that my dealer has a good service dept.

 

[JROG1721]

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.

Im having the exact same problem on M7060. Did you get ur issue resolved? If so, what was the fix? Tks!

 

[BufordBoone]

Yes. I explained it in the above posts. Fuel injector issue. Dealer knew exactly what it was. Covered it under warranty.

 

[Power2ll]

What did you ever come up with on this problem I am having the exact same issue

 

[BufordBoone]

As I stated in the post immediately above your question:

"Fuel injector issue. Dealer knew exactly what it was. Covered it under warranty."

Also posted earlier was that they changed the fuel injectors.

I hope you get yours repaired under warranty as well.