Bad Valve somewhere?

[Bobcat 763]

Evening folks, 763 Bobcat, when it's running the left wheels want to spin backwards like I'm pulling the handle back. I was hoping it was a linkage problem, but that seems fine. It does this on start up and after it has reached running temps. I'm hoping one of you has had this problem, and can steer me in the right direction. I'd like to get one more season out of this machine. Might as well break down and pick up a service manual as well. Thanks in advance, Larry

 

[Tazza]

Sounds like the neutral adjustment is out. I assume if you push the stick forward a little it stops?

 

[Bobcat 763]

Sounds like the neutral adjustment is out. I assume if you push the stick forward a little it stops?

Yes, I have to push the stick forward just to start it. If I don't it'll bog down and die before I can throttle up.

 

[Bobcat 763]

Yes, I have to push the stick forward just to start it. If I don't it'll bog down and die before I can throttle up.

And speaking of throttling up. My throttle will go down about half way on it's own. Any thoughts on that? Should I start a new thread on this?

 

[Tazza]

And speaking of throttling up. My throttle will go down about half way on it's own. Any thoughts on that? Should I start a new thread on this?

No need for a new thread. There should be a screw on the throttle handle in the cab you tighten up to increase the friction, it shouldn't slide back when it's tight enough.
You will need to adjust the neutral as well. Block it so the wheels are all off the ground. Lift the cab and you will need to adjust the stops on the pump. This sets neutral when the levers are let go. I haven't done it in a while, but start the machine, release the brake so the wheels can turn. Loosen the 4 bolts on the top of the centering plate on the pump (the part that moves with a spring on the left). Move the stop on the right side while looking at the pump so it site flat against the pintle arm that is attached to the steering lever. Adjust it till the wheels do not move. Tighten up the bolts. Repeat till the sheels on that side do not move when you let the stick go. Push forward and backward then release, it should still stop moving. Same with the other side. Repeat till both sides are still when the levers are let go.
It's not hard, but can be fiddly to get just right

 

[Bobcat 763]

No need for a new thread. There should be a screw on the throttle handle in the cab you tighten up to increase the friction, it shouldn't slide back when it's tight enough.
You will need to adjust the neutral as well. Block it so the wheels are all off the ground. Lift the cab and you will need to adjust the stops on the pump. This sets neutral when the levers are let go. I haven't done it in a while, but start the machine, release the brake so the wheels can turn. Loosen the 4 bolts on the top of the centering plate on the pump (the part that moves with a spring on the left). Move the stop on the right side while looking at the pump so it site flat against the pintle arm that is attached to the steering lever. Adjust it till the wheels do not move. Tighten up the bolts. Repeat till the sheels on that side do not move when you let the stick go. Push forward and backward then release, it should still stop moving. Same with the other side. Repeat till both sides are still when the levers are let go.
It's not hard, but can be fiddly to get just right

Thanks for the help Tazza, I'll try that this weekend. Hopefully the throttle fix is that easy. What a pain that is, it got so irritating that I ended up wrapping a string around it to keep it going full throttle. Thanks again, Larry

 

[Bobcat 763]

Thanks for the help Tazza, I'll try that this weekend. Hopefully the throttle fix is that easy. What a pain that is, it got so irritating that I ended up wrapping a string around it to keep it going full throttle. Thanks again, Larry

I got it back to neutral today, you were right about it being fiddly. I had to go back and forth between left and right about 4 times before both wheels stopped spinning. I also had a lose pintle arm, glad that didn't get too worn to where it needed replacing. But all in all it was an easy fix. Thank you very much, Larry

 

[Tazza]

I got it back to neutral today, you were right about it being fiddly. I had to go back and forth between left and right about 4 times before both wheels stopped spinning. I also had a lose pintle arm, glad that didn't get too worn to where it needed replacing. But all in all it was an easy fix. Thank you very much, Larry

No worries, glad it is fixed.
Keep an eye on the pintle arm, if it wears and gets loose, it will need replacing.
I was lucky enough to have gear to repair mine. I set it up in the mill and squared the holes back up so i could install shims made from metal strapping. Worked a treat, still rock solid.