Any diesel mechanics in here?

[Blinky]

Apply power to the drive motor with your power probe. If it doesn't run, you have a bad drive motor......assuming you did confirm good ground and power going into motor. Confirm with resistance test via voltmeter

Check/test any relays/fuses and switches first

It may just be a faulty relay, so make sure you test those before you buy anything

Does it being hydrostatic change anythin? It uses hydraulics to drive the motors (i think)

[uptown]

Does it being hydrostatic change anythin? It uses hydraulics to drive the motors (i think)

It could, but a faulty pump would blow fuse or trip the relay...that's why ya need to check them 1st. As the fluid flow will be controlled/directed electrically...

Also, you may have to check for fluid flow in all hoses to narrow down where the fluid flow stops. Each direction should have it's on isolated path of flow..i.e up/down, forward/back and in/out if equipped.
If any battery power goes to control levers, check that too. All depends on how new the forklift is. The new one's can get pretty stupid sometimes with all of the electrical circuits and computers these days. John Deere is making things that absolutely can't be repaired unless you take it too them..(computer stuff). Other companies have been following suite.

[Blinky]

It could, but a faulty pump would blow fuse or trip the relay...that's why ya need to check them 1st. As the fluid flow will be controlled/directed electrically...

We assumed the pump was good via the mast but like our loaders it also has a charge pump. Just adjusted boost and with some help on the inching valvve (flathead driver) it gets great boost, more than enough to change gears. From reading the diagram and legend, there are no relays / fuses for the drive motors, only the transmission cut off relay and e valvve. The relay is good, even clicking with gear changes. I will look at the schematic but i think its solely hydraulic. (Again, im 6 weeks into this job from never turning a wrench  )

[uptown]

We assumed the pump was good via the mast but like our loaders it also has a charge pump. Just adjusted boost and with some help on the inching valvve (flathead driver) it gets great boost, more than enough to change gears. From reading the diagram and legend, there are no relays / fuses for the drive motors, only the transmission cut off relay and e valvve. The relay is good, even clicking with gear changes. I will look at the schematic but i think its solely hydraulic. (Again, im 6 weeks into this job from never turning a wrench  )

Okay good, electric good, Next check for pinched hose or clogged fluid filter if the system......it u havent already

[uptown]

 Under full disclosure: I was called a mechanic at work and did work on Diesel engines. Retired 2 yrs ago. I rebuilt locomotives and my job was responsible for the air system. I was a air mechanic. I probably should of told you that first. 

[Morpheus]

ZZZZZZZZZ

[Blinky]

Under full disclosure: I was called a mechanic at work and did work on Diesel engines. Retired 2 yrs ago. I rebuilt locomotives and my job was responsible for the air system. I was a air mechanic. I probably should of told you that first. 

Nah I greatly appreciate the pointers,  turned into a crazy day. for whatever reason, after idling the machine for 30+ the muffler was extremely hot when i rested my entire forearm on it. Weird how that works.

Only filter left was main circuit which i was avoiding. after going shoulder deep in her, the filter was actually 10 / 10 perfect. shocking. replaced it anyway and moved onto the control unit / servo valve for F and R as its next on the list..

I greatly appreciate the pointers.

And 100% can appreciate you working the air systems cuz just F that in general lmao.

 

[Blinky]

ZZZZZZZZZ

Nah, the motor makes more of a DERDERDERDERDERDER kinda sound. Close tho!