3PH lower arms died

patrick_g · Dec 30, 2009

So I'm driving across a pasture through the snow (left over from our white Christmas) with the brush hog/hay handling counter weight up in the air and hit an irregularity in the surface contour hidden by the snow. BAM!! the lower arms are suddenly fully lowered and inoperative and brush hog is in the dirt preventing the tractor from moving much. I recycled the 3PH raise and lower hydraulic control and got no reaction. The 3PH arms seem totally dead.

Luckily I have Pat's easy change hitch and hydraulic top and tilt so I was able to maneuver the implement sufficiently to get free of it and drive away.

I think this is going to leave a bruise on my wallet. Anyone care to guess what was damaged?

This is not a good time to have the tractor in the shop as I need to put out 2-3 big round bales (1,000-1,200 lbs each) about every other day.

Tractor is Kubota Grand L 4610HSTC (about 40 HP PTO, Hydrostat tranny, and cab.)

Pat

RickB · Dec 30, 2009

You leave us guessing what make and model tractor you are having problems with. I'll guess the safety valve for the hitch cylinder circuit opened under shock load and failed to close.

patrick_g · Dec 30, 2009

RickB said:
You leave us guessing what make and model tractor you are having problems with. I'll guess the safety valve for the hitch cylinder circuit opened under shock load and failed to close.

Sorry Rick, I have added Tractor info now.

Pat

Egon · Dec 30, 2009

For starters take a look at the schematic if you have one. Then phone the Service Manager at the Dealer.

Haven't got a clue; but can you lift one arm and see if the other arm follows or if they can be moved independently.

You may have to put the Dodge to use pulling bales.

JohninCT · Dec 30, 2009

A similar thing would happen on our Kubota B1750 when the loader valve got stuck. The loader valve would take all the hydraulic flow and would drop the 3 point and not let it raise. I woudl cycle/jiggle the loader valve handle to get it to free and the 3 point working. Then lube the loader valve slides with a spray or two of WD 40 to keep it freed up.

patrick_g · Dec 30, 2009

Egon said:
For starters take a look at the schematic if you have one. Then phone the Service Manager at the Dealer.

Haven't got a clue; but can you lift one arm and see if the other arm follows or if they can be moved independently.

You may have to put the Dodge to use pulling bales.

Too muddy to get the dodge to the hay barn without ruining a lot of pasture and dragging bales through the mud driving backwards using the winch line would not be among the first few choices.

I fear some sort of catastrophic failure since the drop of the arms coincided with the tractor taking a good bump from uneven terrain hidden under the snow. I'll try wiggling all the controls just in case... wouldn't want to pass up a trivial fix to spend $ and time at the dealer and driving 70 miles RT in the weather we are having if not needed.

I don't recall seeing schematics for the hydraulics. I'll call the dealer shop and see if they have a clue.

Pat

groundcover · Dec 30, 2009

Do you have a knob under your seat (between your knees) to adjust the speed of the 3pt hitch? Check to see if that got moved . Also might have a little moisture in the hydro oil that froze up, get it in, warm it up, change hydro oil and filters. A little ice can go a long way to ruin your day when it's in the wrong place !

patrick_g · Dec 30, 2009

groundcover said:
Do you have a knob under your seat (between your knees) to adjust the speed of the 3pt hitch? Check to see if that got moved . Also might have a little moisture in the hydro oil that froze up, get it in, warm it up, change hydro oil and filters. A little ice can go a long way to ruin your day when it's in the wrong place !

Yes, I have such a knob and it takes many revolutions to go from max to min. It is unlikely(nearly impossible) it would just accidentally get turned many revolutions.

Every thing was working normally, I put out 3 bales of hay using the FEL with hay spike and was just transiting a pasture when I banged a bump pretty hard. Seems like something broke but it could be a hydraulic malfunction.

Pat

Carl_NH · Dec 30, 2009

PatrickG

I had my old L175 hydraulic lift apart to replace the seals and they are pretty robust piston/arm setup that I find it hard to beleive it would shear the pin. Its not real difficult to remove the top but I would take off the oil fill port and take a look inside before removing the top.

Here is a link to Messicks parts list for your tractor - you will see the roll pin in the shaft but to shear that would take a significant upward thrust on the 3PT (versus the typcial downward push to raise) to shear that pin.

Kubota L4610DT-HST-C Parts Diagrams

There is a draft control feedback lever that could be the culprit too.. GOod luck and I hope you have a warm place to work!

Soundguy · Dec 31, 2009

With the shock load issue.. I'd have to ditto what Rick said about the safety valve.

that thing got an inspection port so you can see into /under the lift cover with a telescoping mirror on a stick.. that and a hyds sceematic and you should be able to see where oil is going out.. and what that means.

soundguy