Bobcat Versahandler V723 No Forward / Reverse after hydraulic fluid change

[paoutdoorsman]

It was time for a fluid change on my V723. No problem right? Drained the tank, pulled and replaced the filter, refilled with new fluid. Afterwards, the boom functions and steering all work as expected, but it will not drive forward or reverse. Doesn't even attempt to move. It was driving fine before the simple fluid exchange. Thoughts?

 

[LouNY]

Not familiar with your unit but hydrostatic drives use a charge pump to make up for fluid loose. On some systems the charge pump is a separate pump which may not be priming. Others will use a low pressure draw off the main pump. If you can see your pump"s" you may be able to crack the discharge on them and see if you have fluid through the pump. Or your service manual may have a priming method.

 

[paoutdoorsman]

Oddly, the service manual doesn't mention anything about priming...

Here is a pic of my pump arrangement. It looks like a larger pump attached to the bell housing, and possibly a smaller pump attached further out. The large hydraulic lines to the transaxle are attached to the end of the larger pump - I drew red lines on them showing where they head to the transaxle at the front of the machine. Any suggestions on what I might be the discharge to crack open?

 

[LouNY]

Most likely not the ones into or from the transaxle. Charge pumps are normally smaller and lower pressure feeds off an auxiliary circuit or pump.