bobcat 753 lift

[ralayton]

bobcat has no lift. tilt works and drive works just no lift up. the lift pedal doesn't seem to have the correct spring to it as the tilt pedal does. i have got it to come up before by cussing at it and when I do get it up then down works just fine. i believe that the problem is in the hydraulic control valve but any ideas would be appreciated. thanks. Russell

 

[Tazza]

Is this a G series? tringular lights? if so, the control block has lockouts to prevent the pedal operating the hydraulics if it senses there is a problem like seat bar not down, no one in the seat etc. Esusally this locks your park brake too though.
If its not a G series, the older ones had a boom lockout coil, which does the same thing for safety reasons. Same sauses, seat bar sensor or seat sensor.
Its somewhere to start.

 

[ralayton]

Is this a G series? tringular lights? if so, the control block has lockouts to prevent the pedal operating the hydraulics if it senses there is a problem like seat bar not down, no one in the seat etc. Esusally this locks your park brake too though.
If its not a G series, the older ones had a boom lockout coil, which does the same thing for safety reasons. Same sauses, seat bar sensor or seat sensor.
Its somewhere to start.

i believe that it is an older model. i do not know the series. the data plate just says 753. I am to believe that all the sensors are working correctly. parking brake works as it should. seat bar is a mechanical lockout. not so sure about the seat sensor. bottom of the seat have a plug with nothing plugged in to it.. the plug is dirty enough for me to think it has never had anything plugged into it. my only problem is lift everything else works ok. thanks again, Russell

 

[mrfixitpaul]

i believe that it is an older model. i do not know the series. the data plate just says 753. I am to believe that all the sensors are working correctly. parking brake works as it should. seat bar is a mechanical lockout. not so sure about the seat sensor. bottom of the seat have a plug with nothing plugged in to it.. the plug is dirty enough for me to think it has never had anything plugged into it. my only problem is lift everything else works ok. thanks again, Russell

It sounds like the detent balls/spring on the lift spool have rusted up. As long as the linkages are all good and the pedal itself isn't sticking on it's pivot. It's a little tricky to replace the balls/spring with the valve in the machine but it is do-able.

 

[ralayton]

It sounds like the detent balls/spring on the lift spool have rusted up. As long as the linkages are all good and the pedal itself isn't sticking on it's pivot. It's a little tricky to replace the balls/spring with the valve in the machine but it is do-able.

so if i remove the lift spool all i need to do is disconnect the lift linkage, remove the retainer and the boot and the spool pulls straight out. I work on airplanes for a living and am trying to fix this machine for the father in law so any information on how to perform this would be greatly appreciated. After I pull it out will it be pretty straightforward how to reinstall the spool detent balls and the spring. I currently do not have a maintenance manual and the parts catalog illustration isnt very clear. Thanks, Russell

 

[skidsteer.ca]

so if i remove the lift spool all i need to do is disconnect the lift linkage, remove the retainer and the boot and the spool pulls straight out. I work on airplanes for a living and am trying to fix this machine for the father in law so any information on how to perform this would be greatly appreciated. After I pull it out will it be pretty straightforward how to reinstall the spool detent balls and the spring. I currently do not have a maintenance manual and the parts catalog illustration isnt very clear. Thanks, Russell

Basically thats how its done. However the spool is drilled cross ways and the detent spring and to tiny balls, that lock into a groove on the cap you see on the back side are a bear to install with the valve in the machine but it can be done. This detent is to lock the pedal in float position. If you don't care about float you can leave them out. If you try to put them in be sure to order spares, you will lose some and they are cheap anyway.
Now back to the original problem. Assuming the foot pedal linkage is free and not binding. Sound like a broken spring that centers the spool in the “hold” position. Or that springs fastener may have come loose. You don't need to remove the linkage or the spool to check this. Just remove the cap on the back side of the valve for that spool. Wrap a rag around it if you want to attempt to save the dentent balls as they will fly out sideways once you pull the cap back (off) far enough. Once the cap is off, inspect the spring and how it pushes against the valve. The problem should be obvious at this point.
You should have new seals for the spool, new centering spring, detent spring and 6 or 8 balls. Maybe a new cap if ts grooved badly from the dentent balls, but I think you can just rotate it.
Some guys have successfully compressed the detent spring and balls into the spool with a wire tie. Other then that the job is pretty self explanatory.
Ken