I bought a Bobcat 743 "project" last fall. It had sat for several years with no cover on the exhaust pipe. Water got in the engine and I ended up with a complete rebuild (expensive). Anyway.. It runs great now and drive is strong forward and reverse on both sides but the lift and tilt seem weak. I finally checked the pressure at the aux port and it reads about 1500# with the right steer lever to the right, nothing to the left. I've unknowing been running it in the right position. The engine loads a little when moving the lever to the right but not much. lift and tilt work in either position. I've read that there is a pressure relief valve but I haven't found it yet. I know the pressure should be around 2500#. I guess i'm not sure where to go from here without buying a new pump that I may not need. Can I check the pressure directly at the pump before it goes to the control block/pressure relief valve.
743 aux hydraulics
- Thread starter ozark18
- Start date
flyerdan
Well-known member
- Joined
- Mar 7, 2009
- Messages
- 983
The relief valve is part of the valve body that runs the lift and tilt. Since it has been running in bypass for so long, it's possible that there is a small piece of debris that is keeping it from closing all the way.
Best thing to do is grab the service book from the manual thread and read up on it, they're pretty good with diagrams and parts views.
Best thing to do is grab the service book from the manual thread and read up on it, they're pretty good with diagrams and parts views.
Thanks. I'll check it out. The valve body is a bear to get at. I see where the hose connects to the lift pump and goes to the valve body. If I could connect my gauge there it would eliminate the pump, or not. Just wasn't sure if it would be safe or damage anything.
I found the relief valve and removed and cleaned it. Didn't make any difference. Still only 1500 psi at aux port. Ordered a new relief valve. Thought better to spend $75 before $600 for a new pump.
