T300 hydraulic issue

[zakscott22]

A friend of mine asked me to look at this thing. They changed the oil pan, had the hydraulic pump rebuilt, plus some other general maintenance stuff. Im sure I'm not getting a full story but supposedly everything worked fine before. It has no lift and no tilt up, will lower and tilt down. Will drive fine without issue. I am getting a 05-15 code for low charge pressure. When going to lift or tilt can hear it load up like there it is deadheading but no lift. If anyone has ideas, pointers, even hydraulic schematics and wiring diagrams that would be greatly appreciated.

 

[flyerdan]

There should be a T300 book in the manual thread that will help with the diagrams and troubleshooting.

 

[Bswwood]

If you have low charge pressure the BICS interlock will not be able to release so no lift tilt. If the pumps have been rebuilt there may be an issue with the charge relief in the drive pump section.

 

[zakscott22]

If you have low charge pressure the BICS interlock will not be able to release so no lift tilt. If the pumps have been rebuilt there may be an issue with the charge relief in the drive pump section.

I checked pressure to the charge pressure sensor, just used my adapters and connected line directly to pressure guage. I am showing no pressure out of the charge pressure line. I'm getting pressure to other lines out of pump and I can feel heat in the lines when I let it run. Just nothing on the charge pressure side. The diagrams i found are split so its difficult to follow the hydraulic schematics. Im leaning towards pulling the charge pressure relief but was seeing if you had other ideas before I do that.

 

[Bswwood]

I checked pressure to the charge pressure sensor, just used my adapters and connected line directly to pressure guage. I am showing no pressure out of the charge pressure line. I'm getting pressure to other lines out of pump and I can feel heat in the lines when I let it run. Just nothing on the charge pressure side. The diagrams i found are split so its difficult to follow the hydraulic schematics. Im leaning towards pulling the charge pressure relief but was seeing if you had other ideas before I do that.

First try to check pressure at the auxiliary couplings. You should have 3000+ psi when auxiliary is activated. If you have pressure there then you know gear pump is good. After confirmation of good gear pump then pull the charge relief. Make sure to check pressure on standard flow not high flow if machine is equipped with high flow.