M7040 Weak, choppy hydraulics

[berrycw2]

Had the hydraulic fluid changed 100 hours ago on my M7040 (2011 model), 3100 hours. Used Kubota filters and fluid. The hydraulic pressure relief value by the rear remotes was adjusted to bring up the pressure a bit as it was noticed that the hydraulic flow seemed a bit weak.

Have not done a lot of work with the tractor over the winter just plowing snow on the farm every couple of weeks. Tractor worked ok up until now. Last used a couple of weeks ago. Now the hydraulics have no power. Pump is whining a bit. Power steering has no power or is very choppy. Fluid is clear, and full. No signs of any leaks.

Dealer mechanic thinks either a clogged filter, or the hydraulic pump has bit the dust. Any other suggestions?

 

[Tx Jim]

Normally hyd pump's don't just suddenly bite the dust! I suggest to perform good hyd diagnostic procedures before entertaining idea of replacing the hyd pump. I suggest checking hyd pressure with a gauge.

I've also owned a ''11 M7040 since 2012. My guess is debris is in hyd relief valve seating area or a hyd control valve is not in neutral position.

Move 3pt control lever forward an inch. If that helps restore hyd pressure then 3pt feedback rod needs adjusting.

 

[TheOldHokie]

Had the hydraulic fluid changed 100 hours ago on my M7040 (2011 model), 3100 hours. Used Kubota filters and fluid. The hydraulic pressure relief value by the rear remotes was adjusted to bring up the pressure a bit as it was noticed that the hydraulic flow seemed a bit weak.

Have not done a lot of work with the tractor over the winter just plowing sn on the farm every couple of weeks. Tractor worked ok up until now. Last used a couple of weeks ago. Now the hydraulics have no power. Pump is whining a bit. Power steering has no power or is very choppy. Fluid is clear, and full. No signs of any leaks.

Dealer mechanic thinks either a clogged filter, or the hydraulic pump has bit the dust. Any other suggestions?

Sounds like the pump is being starved of oil. Measure the flow coming from the pump. Do you have a loader and is this a cab or open station model?

Dan

 

[berrycw2]

Changed the filters, and the hydraulics better than ever. I don't know the maintenance history prior to buying this tractor. It had 2800 hours on it when I got it, and we put a few hundred hours on it since. So I don't know if it is now completely sorted out or not. We shall find out.

Thanks for the suggestions.

 

[berrycw2]

Sounds like the pump is being starved of oil. Measure the flow coming from the pump. Do you have a loader and is this a cab or open station model?

Dan

It is a cab with FEL, plus a BH92. We measured the pressure after the filter change and it was up to normal pressure.

 

[TheOldHokie]

It is a cab with FEL, plus a BH92. We measured the pressure after the filter change and it was up to normal pressure.

Thats great and glad your up and running.

But I was talking measuring pump flow rate not pressure. My guess is your old filter(s) were clogged and the pump was getting starved of inlet oil.

Dsn

 

[berrycw2]

Had the filters cut open and they were full of a grey sludge material (maybe water?). This seemed to be a bit odd as the hydraulics were working fine prior to the dealer hydraulic change of fluids and filters. As mentioned before I ran it for 100 hours before they clogged completely. I didn't use any other additional hydraulic powered attachments during that 100 hour period either. So either there was existing sludge in the system or the new hydraulic oil was contaminated. Oil is clear on the dipstick, and the oil looked good for the bit that leaked during the filter change. Kubota oil and filters were used. Not sure on this one as I have no idea what the maintenance on this tractor was for the first 2800 hours of its life.

Going to run it for a bit and see how it goes. Now that I know what signs to keep an eye out for when using it, as hindsight suggests this was a gradual failure and not all of a sudden.

 

[TheOldHokie]

Had the filters cut open and they were full of a grey sludge material (maybe water?). This seemed to be a bit odd as the hydraulics were working fine prior to the dealer hydraulic change of fluids and filters. As mentioned before I ran it for 100 hours before they clogged completely. I didn't use any other additional hydraulic powered attachments during that 100 hour period either. So either there was existing sludge in the system or the new hydraulic oil was contaminated. Oil is clear on the dipstick, and the oil looked good for the bit that leaked during the filter change. Kubota oil and filters were used. Not sure on this one as I have no idea what the maintenance on this tractor was for the first 2800 hours of its life.

Going to run it for a bit and see how it goes. Now that I know what signs to keep an eye out for when using it, as hindsight suggests this was a gradual failure and not all of a sudden.

Makes perfect sense - oil starvation caused by clogged filter(s). That grey sludge sounds like a water in oil emulsion possibly combined with additive dropout. It came from somewhere and there may be more to come. I would be thinking about a thorough flush and fluid change in addition to new filters.

Dan

 

[Tx Jim]

I agree as it sounds as if hyd oil was contaminated with water. I suggest to check trans case vent to be sure it's not clogged. One could test old hyd ooil by placing a small amount in a pan then heating to determine if heated oil emitted a crackling sound.