cat 225 51u725 will not tram

[Vernon Lowe]

neither side will turn.when i step on the pedal the motor loads and the tram motor hoses flex. i checked the oil in the final drives and there's no metal. How and where do i check the prssure to the drive motors? I also think the lift cylinder is slow,is the boom lift and tram motors controlled by the same pump?

 

[Nige]

Attached the Cycle times and Test & Adjust procedures for the hydraulic system.
You might be well advised to start with cycle times on the travel motors then move to measuring the case drain flow from them before moving on to pressure tests.

The usual way to measure travel motor pressure is to jam a track pin, towing pin, etc, into the teeth of the sprocket then rotate the travel motor so the pin becomes jammed.

 

[Chrisso]

Those test & adjust docs are excellent. Wish they still made excavators like these.

As per what Nige said, start with cycle times and case drain flow. Take a case drain line off each drive motor. If oil shoots out while trying to track the machine you have a problem.

Another easy check is the track brake. Loosen the hoses at the track brakes, stand well away and start the machine, try to track. Things should get messy. If not, track brakes are engaged.

Is there a chance someone else has worked on this machine and left the little screw wound in on the track brake valve?

 

[Vernon Lowe]

Attached the Cycle times and Test & Adjust procedures for the hydraulic system.
You might be well advised to start with cycle times on the travel motors then move to measuring the case drain flow from them before moving on to pressure tests.

The usual way to measure travel motor pressure is to jam a track pin, towing pin, etc, into the teeth of the sprocket then rotate the travel motor so the pin becomes jammed.

thank you

 

[Vernon Lowe]

Attached the Cycle times and Test & Adjust procedures for the hydraulic system.
You might be well advised to start with cycle times on the travel motors then move to measuring the case drain flow from them before moving on to pressure tests.

The usual way to measure travel motor pressure is to jam a track pin, towing pin, etc, into the teeth of the sprocket then rotate the travel motor so the pin becomes jammed.

my question for that is how can i rotate the travel motor and jam a pin if the motors won't turn the tracks?

 

[Vernon Lowe]

Those test & adjust docs are excellent. Wish they still made excavators like these.

As per what Nige said, start with cycle times and case drain flow. Take a case drain line off each drive motor. If oil shoots out while trying to track the machine you have a problem.

Another easy check is the track brake. Loosen the hoses at the track brakes, stand well away and start the machine, try to track. Things should get messy. If not, track brakes are engaged.

Is there a chance someone else has worked on this machine and left the little screw wound in on the track brake valve?

no one has worked on it that i'm aware of. I loaded a load of dirt and backed the machine up.delivered that load of dirt and went to move it again and it got to moving real slow and then stopped and won't budge now.

 

[Nige]

my question for that is how can i rotate the travel motor and jam a pin if the motors won't turn the tracks?

Try lifting the tracks off the ground one at a time. Will they turn then.?

 

[Vernon Lowe]

Try lifting the tracks off the ground one at a time. Will they turn then.?

no

 

[Vernon Lowe]

i did take the 2 bolts out of 1 track motor and hit the pedal and that motor will turn both directions on the brake housing a couple inches til the hoses catch it

 

[Nige]

Well if the tracks won't turn then you need to get a pressure gauge on the motor as per the procedure above. Report your results for both sides.

Attached the System Operation for the hydraulics so you can understand how it works. There are a total of 4 pumps n that machine.

 

[Vernon Lowe]

Well if the tracks won't turn then you need to get a pressure gauge on the motor as per the procedure above. Report your results for both sides.

Attached the System Operation for the hydraulics so you can understand how it works. There are a total of 4 pumps n that machine.

I got the tram motors to turn briefly by turning out the screw on the brake valve,I put the cover back on the tram motors and now it won’t do anything. Does that screw have anything to do with the pressure to the brakes?

 

[Chrisso]

Page 57 of the Systems Ops Nige posted explains it better than I can. That screw is there to provide means of preventing track movement during testing. You achieve the same thing by jamming something in between the sprocket and track chain as mentioned by Nige earlier.