eaton motors on mulching head setting them up

[idahohydroax]

hydroax mulcher bought the machine and both motors were blown. got 2 rebuilt ones hooked them up a to b ports they are bi-directional they spin up fine but when i switch the flow off the head comes to a stop pretty quick and you can hear a chattering or vaning sound on the secondary motor it just doesnt sound right?
thanks

 

[J_J]

Do you have a motor spool valve for that motor?

You might need a cross over relief valve across the motor.

 

[oldnslo]

It looks like there are cross port relief valves on the end of the motor. What can be happening is the motor is cavitating during rundown since most motors require a pressurized inlet at higher RPM's during this braking or rundown time. Look at an Eaton data sheet on those motors. It should have a chart or graph showing required inlet pressure Vs RPM for braking or run down conditions. If this closed loop hydrostatic drive the charge pump pressure should work for this unless there is significant flow loss to tank.

I believe that due to safety concerns there is a run down maximum time so using a motor spool with out some braking function typically is not permitted.