1755 - Over / Under

[agonair]

Recently acquired a 1755. Not much to look at but mechanically it is solid. I have a question on the over / under. This only
happens when you turn right, no matter what range, it will act as if it is jumping out of range. It does not do it turning left.
If I place it in 6th gear, I can ride the brake in all three ranges and not make it slip.
A mechanic friend told me it dould have to with oil pressure and flow.

Thoughts?

 

[Cash4Toys]

O/U is a completely separate system, has it's own oil and cooler, has nothing common with the rest of the tractors hydraulics. That must be deeper in the drive train, like in the differential. Jack up the rear, and rotate the wheels one side at time while keeping the opposite side stationary, listen and or feel if their is difference from side to side.

 

[Mike(NEOhio)]

I'm not familiar with the O/U/D but could there be something hitting the shifter linkage on a right turn?

 

[scootergmc]

What do you mean by jumping out of range? Do you mean the tractor will stop? You talk about steering then gears then braking so I'm a little confused.

 

[rrlund]

Just for the heck of it, run the right side up on a side hill and see what happens. I'm wondering if the oil is moving to the left side and something is causing it not to be picked up? As you know, there's not much in those units to start with.

 

[Gary Mitchell]

Definitely a Duane Starr question. gm

 

[agonair]

Let me clarify:
I can place the tractor in any gear 1 - 6 and place it in under, direct, and over...ride the brake and it does not slip.

I can place the tractor in any gear 1-6 and place it in under, direct, and over and turn the tractor to the right and it acts like it is falling back...example, in over, it will fall back to direct or under. Straighten it out and it return to where it was.

Turn left...it works normally.

Understand?

 

[scootergmc]

OK, that makes sense. And that's weird.

Are the lines hooked up correctly to the cooler?

 

[scootergmc]

And I ask not knowing if you have the two separate coolers or the big combined cooler. I don't know if the 1755 ever came with the combined cooler. If it does, or has been retrofitted, I'm thinking that the O/U pressure is dropping when a demand for steering is there because the lines are hooked up incorrectly. I would imagine there would be other issues as well. That's where my thoughts are coming from.

 

[Mike(NEOhio)]

I'm just guessing here. Familiar with HP but hot the three speed. The lever is along side the throttle isn't it? Can you hold it in place when you make the left turn or is it forcing your hand?

 

[Cash4Toys]

If that is as factory original,what your saying is not possible. The o/u is an isolated unit.
It has its own oil supply, and only two (2) external lines for cooling,feed and return.
If by chance, someone cross plumbed a hydraulic line into a steering line, you would think the o/u unit would eventually be overfilled and be blowing oil out the breather. Steering fluid lines run from back of dash above the engine. then down the left front of the engine. Hydraulic cooling lines run along the left inside of the tub, and the o/u cooling lines on the front right side of the o/u that go up, tight against the front of the fuel tank then run over the engine to the grill and then drop down into the cooler.(as viewed from sitting in seat) There is another bleed off line from the steering cylinder, low preasure that also runs along the right side of the tub back to the the hydraulic case. Makes it hard to cross plumb. Question; by chance, if the right turn steering hose was replaced behind the dash, and lets say its not of proper length, so when preasurized to turn right, it swells/gets firm and then bumps the control linkage so as to make a mechanical shift? Look for lines rubbing on o/u shift linkage.