losing power in Hydraulics

[JeepCJ]

hi all,

I have a 1999 bobcat skid steer (773 i believe) it runs fine for the first 1-2 mins with power in the levers but then it dies down to nothing... the engine seems to have no problems at all. then if i keep the levers foward the power comes back in the hydraulics for a bit then leaves again?? any suggestions.. is there a filter to check or do you figure a weak pump??

Thanks in advance

p.s great site by the way

 

[greywynd]

First thing I would check are the fluid levels, then the filters. Sounds like it might be starving for oil somewhere along the line.

 

[JeepCJ]

where are the filters located for the hydro fluid?? levels are good ...actually there is a little too much in there

 

[bob]

As a new member, I can only add to a thread. I have a 2002 763 Bobcat. The battery has required jumping for the last year or so (used infrequently). It always has enough power to turn on the "dashboard" lights and run the count down on the glow plugs. And it always jump starts off my Ford 150. Today I left the key in the "on" position while the jumper cables were hooked up. Now no lights come on, no beep when key turned to "on." Fuses below seat look ok, but I don't know how to remove the 100 amp fuse to check it. Nor do I know how to check the relay switches under the seat. All help and suggestions will be appreciated.

 

[bobcatmechanic]

first on the 773 do you hear a belt squelling if you do check the drive belt tension it may be loose and thats why you have low power in the drive area also change the hydraulic filter that may help also if neither one of those helps take it to the dealer and let them look it over it may be a pump problem internally rotating groups going bad also try pulling the case drain filters there are 2 they will either be located at the drive motors if you pull the 2 covers one on each side in between the wheels look for a silver cylinder that is about 3 to 4 in long and about 2in around it will take a 3/4 or 11/16 wrench to remove the hydralic lines to them then a 1 1/2 wrench and a 1 3/8 or a vise and one or the other wrench look for metal shavings in them a little will be normal a lot is a bad sign also when you move the sticks to full stroke and then hold one side full stroke and back off the other one slowly does it take alot of movement to see a diffrence in wheel speed as far as a turn or as soon as you move the stick it starts to turn because it may aslo be in the drive motor needing resealed i had to reseal one on a 873 about a week ago the seals got week and it would drive funny fine at first and then you could feel it slow down and start to track to one side instead of going straight.


now on the 763 get a new battery and have the alt checked take it to the dealer or o riellys and get it tested its better to take a vat and test it one the machine and see which is bad sometimes its both other times its the bettery and the alt both bad but if your not using the machine all that often get a trickle charger and put on to keep the battery up batteries naturally drain over time and need rechaged periodically its like if you park you car for 2 years with a new battery and dont start it and then go out and try to it will have drained and be dead but if you start it once or twice a week and let it run for a half hour and charge up it will still start every time with everything else being right but i would have the battery checked it has to be charged before you can check it because if you take a dead battery in and check it it will test bad every time so charge it on med charge for an hour and a half then check it

 

[JeepCJ]

thanks for the info...much appreciated ...i'll keep ya posted

 

[bobcatmechanic]

also on that they have 12 jic fittings which are a flared fitting for the sealing on the drive motor i believe if you pull one off and look or just take them off at the hydrostatic pump witch is right straight in as you lift the cab put a cap or plug on the fittings on the hydrostat which would be a cap you can get them at any bobcat dealer parts store maybe or any hydraulic shop when you do start the engine and stroke the sticks at full throttle it should bog the engine and kill its self when you stroke the levers fully that will tell you if its in the hydrostat or some where else if it kills it the rotating groups are good if not if one side does and the other doesn;t then the side that doesn't is weak and needs replaced or looked at at the least do one side at a time stroking it you can cap both at the same time and do the test all at once as far as capping the pump it will take an 1 1/4 wrench to take the lines off

 

[bobcatmechanic]

also on that they have 12 jic fittings which are a flared fitting on the hose for the sealing on the lines to the drive motor. if you pull one off and look or just take them off at the hydrostatic pump witch is right straight in as you lift the cab put a cap or plug on the fittings on the hydrostat which would be a cap you can get them at any bobcat dealer parts store maybe or any hydraulic shop when you do start the engine and stroke the sticks at full throttle it should bog the engine and kill its self when you stroke the levers fully that will tell you if its in the hydrostat or some where else if it kills it the rotating groups are good if not if one side does and the other doesn;t then the side that doesn't is weak and needs replaced or looked at at the least do one side at a time stroking it you can cap both at the same time and do the test all at once as far as capping the pump it will take an 1 1/4 wrench to take the lines off

 

[djbrasseur]

good luck