Help hydraulics not working after fluid replacement

[SeanMonty]

I managed to rip the hydraulic inlet pipe off the side of the transmission when I hit a stump in tall grass. (pipe that runs from transmission to the filter). All the fluid leaked out. I bought a new pipe, put it back in place, cleaned the filter, and put in 11.6 gallons of hydraulic/transmission fluid as recommended . The engine runs fine and I can drive it in forwards and reverse, but the FEL, rear 3 pt hitch, and steering will not work. Unfortunately it is stuck in a place where I can not get my trailer back there to take it into a dealer. And with the steering not working, I can not drive it out to a better spot.

My thoughts were
1. Do I need to bleed the air out somewhere? I can not find a bleed screw or reference in the manual.
2. Did the pump go bad from running with no fluid?

Any advice would be appreciated. Even I can just get the steering working, I could get it to the point where I could get it on a trailer to be serviced.
Thanks,
Sean

 

[Dave_eng]

For generations tractors were steered by using individual rear brakes.

Your tractor will have a lever locking both brake pedals together. as it is the safe way for higher speed travel.

Flip lever to the side so each brake works on its own. Use this method in 2WD.

Use 1st gear. Push hard on one brake while going forward and see if you cannot maneuver it that way to get it on a trailer.

Dave

 

[Kennyd4110]

My thoughts were
1. Do I need to bleed the air out somewhere? I can not find a bleed screw or reference in the manual.
2. Did the pump go bad from running with no fluid?

1) The systems are self-purging, so there is no need to bleed any air.

2) Possibly, how long did the engine run with no fluid?

 

[Dave_eng]

I managed to rip the hydraulic inlet pipe off the side of the transmission when I hit a stump in tall grass. (pipe that runs from transmission to the filter). All the fluid leaked out. I bought a new pipe, put it back in place, cleaned the filter, and put in 11.6 gallons of hydraulic/transmission fluid as recommended . The engine runs fine and I can drive it in forwards and reverse, but the FEL, rear 3 pt hitch, and steering will not work. Unfortunately it is stuck in a place where I can not get my trailer back there to take it into a dealer. And with the steering not working, I can not drive it out to a better spot.

My thoughts were
1. Do I need to bleed the air out somewhere? I can not find a bleed screw or reference in the manual.
2. Did the pump go bad from running with no fluid?

Any advice would be appreciated. Even I can just get the steering working, I could get it to the point where I could get it on a trailer to be serviced.
Thanks,
Sean

Sean
More info please.
Is your tractor 2WD or 4WD.
What equipment on your tractor. A FEL? Rear remotes.

The steering should be able to move the front wheels but it will take either high effort or many turns as the steering valve turns into a manual pump so you don't loose steering completely with a hydraulic failure.

Try the steering with the engine off and see if you can make the front wheels turn. The steering design is such that if you are going down a hill and run out of fuel or the engine stalls, you can still have some control over staying out of the ditches.

I cannot find any manuals on line in the usual places for your MX4700

It would help if you can post some photos of the underside of your tractor and then some side views of the pump(s) and filters.

Dave

 

[SeanMonty]

Thanks for the info about the self purge
2. I think I drove it about 70 feet before the steering went out and I figured out what had happened. I know it is hard to believe that I didn't notice 11 gallons of fluid leaking out!

 

[SeanMonty]

Dave - Thanks for the advice about trying to steer with the brakes. I had not thought of that and will give it a try
It is a 2wd with FEL and no rear remote. I will try to get some pictures.
I was able to spin the steering wheel around several times in each direction without the front tires moving at all.

 

[North Idaho Wolfman]

Sean
More info please.
Is your tractor 2WD or 4WD.
What equipment on your tractor. A FEL? Rear remotes.

The steering should be able to move the front wheels but it will take either high effort or many turns as the steering valve turns into a manual pump so you don't loose steering completely with a hydraulic failure.

Try the steering with the engine off and see if you can make the front wheels turn. The steering design is such that if you are going down a hill and run out of fuel or the engine stalls, you can still have some control over staying out of the ditches.

I cannot find any manuals on line in the usual places for your MX4700

It would help if you can post some photos of the underside of your tractor and then some side views of the pump(s) and filters.

Dave

Hydrostatic steering, which this model is equipped with, will not work if the system got air in it, as it would with a broken suction line, it's 100% hydraulic, no mechanical input.

 

[North Idaho Wolfman]

I managed to rip the hydraulic inlet pipe off the side of the transmission when I hit a stump in tall grass. (pipe that runs from transmission to the filter). All the fluid leaked out. I bought a new pipe, put it back in place, cleaned the filter, and put in 11.6 gallons of hydraulic/transmission fluid as recommended . The engine runs fine and I can drive it in forwards and reverse, but the FEL, rear 3 pt hitch, and steering will not work. Unfortunately it is stuck in a place where I can not get my trailer back there to take it into a dealer. And with the steering not working, I can not drive it out to a better spot.

My thoughts were
1. Do I need to bleed the air out somewhere? I can not find a bleed screw or reference in the manual.
2. Did the pump go bad from running with no fluid?

Any advice would be appreciated. Even I can just get the steering working, I could get it to the point where I could get it on a trailer to be serviced.
Thanks,
Sean

How did you "clean the filter", it's a spin on replaceable filter?

If you have fixed all the suction side of the system, and it's vapor locked, on some models it happens, go to the pump delivery pipe (small pipe out of the bottom, follow it back till it gets to the hydraulic outlet block, then loosen the banjo bolt on the line, run it and within a few seconds fluid should flow, shut it off and tighten the fitting, everything should come back on line.

 

[SeanMonty]

So i disconnected the hydraulic line right before it enters the pump. This line was dry. I filled it with hydraulic fluid to prime the pump and it started working again. Must have been air lock leading into the pump. It seems to work Ok now. At least well enough to drive the tractor back up to the road and garage to work on it.
Thanks for the help.