Skid Steer Wheel turns forward when lever is moved backwards!

[finchm]

This is a New Holland L35 Skid Steer with a Vickers transmission. It works properly on flat ground. Goes forwards, backwards, turns both directions just like you would expect.

The problem is when I am on a hill and the machine is moving forwards down that hill. If I pull the left steering arm backwards to reverse the wheel direction, the left side motor now acts is if I am pushing the lever forward. The right side works normally. Basically, if the left side wheels are moving forward from an external force then the steering arm keeps the wheels moving that same direction. I assume that something is messed up in the left side pump/motor setup. What should I look for when opening this guy up? Is this a pump issue, motor issue, valve issue? Does this condition have a common name?

 

[oldnslo]

Does the left side have full power when pushing into a pile?

If you try to pull something do you have power going in reverse?

First thing I would inspect / suspect is the connection of the control linkage to the pump to verify that a pin or key has not sheared.

 

[finchm]

Does the left side have full power when pushing into a pile?

If you try to pull something do you have power going in reverse?

First thing I would inspect / suspect is the connection of the control linkage to the pump to verify that a pin or key has not sheared.

It seemed to have decent power in forward and reverse when I last used it. The external mechanical linkages are all in good shape. They are keyed and there is no slippage.

 

[wdchyd]

Seems like you are losing charge pressure on that left side, maybe too much blow by in the pump rotating group creating excess case flow and cavitating the suction side of the pump during the overrunning load going downhill.

Just a guess, the longer you run it may have the pump committing harakiri.

 

[oldnslo]

Before tearing anything apart I would suggest checking for power at the left side vs right side both forwards and reverse. I.e. will it easily spin the tires pushing into something or pulling on something. Does seem like engine strains similar forward vs reverse?

Any different or strange sounds forward vs reverse.

If pump or motor is going bad causing loss of charge pressure it should show up under load.

Maybe check when oil is cold and warmed up.