2005 Cat 257b No right track then no hydraulics at all

[Yaterpillar]

was using it to clear my property and have noticed that it is real weak when trying to go forward or back ward and turn at the same time. Have been having to go forward or back and then turn.

Then some times left and right steer wouldn’t work randomly

Then right track wouldn’t respond unless I gave the engine more throttle and then it would jerk back into action and work for a while

After 30 mins of that.. lost all hydraulics. Everything. No hydraulic whining. No nothing. Dead in the water with everything.

This unit has a 86hp Yanmar swapped engine in it just FYI

Help? Bad engine/pump coupling? Right final drive crapped out??

Oil levels are full.

 

[Nige]

After 30 mins of that.. lost all hydraulics. Everything.

Including all bucket functions.?

If yes, have someone observe the cooling fan under the radiaotr when you start the engine. Does the fan start turning immediately.?

 

[Yaterpillar]

I’ll check here in a few hours. I lost all movement in the drives but my bucket/arms worked so I turned it off. Cranked it back up and nothing worked. No drives and no bucket tilt or arms. I’m guessing they moved the first time because of the accumulator. The joysticks are just dead now. Even when I turn the parking brake off, it does not feel like it does anything like it used to just feels like you’re a flipping a dead switch.

I’ll check the radiator fan when I get home

 

[Nige]

I’ll check the radiator fan when I get home

If the fan does not turn when the engine is started then the most likely cause is that the coupler has failed.