Bobcat T300 stalls under load and hyd. fluid seems to heat up fast.

[ronniebrugh]

2005 T300 new hydrostatic and gear pump, drive motors, hoses, case drain and hyd. filters, flushed oil cooler, new brake valve assy., new main relief valve, charge pressure good...
if you move either stick or both forward it stalls out.... and fluid seems really hot... thinking flow restriction somewhere?

 

[Jabonee]

Sounds like the brakes are not releasing. Do you have a porta-power to test?:confused3:

 

[ronniebrugh]

yes I have portapower, and brakes are releasing. if the machine is on jack stands you can give it full stick with out stalling. this machine has been in salt too. I am considering maybe the track rollers are binding...

 

[Jabonee]

yes I have portapower, and brakes are releasing. if the machine is on jack stands you can give it full stick with out stalling. this machine has been in salt too. I am considering maybe the track rollers are binding...

With that being said I still think the brakes are not releasing or better yet being overwhelmed by the track motors. Is this a 2 speed unit and does it have a lot of hours? If you have a high enough pressure gauge and can tee into the track motor case drain line that will tell the story. Basically what I'm saying is the track motors can leak by so bad that the 400psi or so pilot pressure is not enough to release the brakes.Sounds like the problem when you said it works OK off the ground(no load)

 

[ronniebrugh]

I can manually apply brake and it will hold(enough to stall engine while on jackstands). Drive motor is new not saying a new one isn't bad though

 

[Jabonee]

I can manually apply brake and it will hold(enough to stall engine while on jackstands). Drive motor is new not saying a new one isn't bad though

Interesting. If you can stall the motor with the park brake on your pumps and motors should be ok. Your having this issue in both forward and reverse? Is this unit manual control or SJC? Can you post the sn#?

 

[ronniebrugh]

it is manual sticks, yes forward and reverse... 525414965

 

[SSdoxie]

Did you replace the motor case drain filters when new motors were installed?

 

[ronniebrugh]

yes replaced bot case drain filters and even pulled them back off and cleaned them to make sure nothing left over in system got in them...