3 spool directional valve not working

kiotiken · Jun 5, 2020

Dave M7040 said:
Not all hydraulic motors have the same requirements in terms of how they are controlled. Some need case drains and others do not as one example.

One issue with motors not experienced by hydraulic cylinders is when the valve returns to the center position the motor is instantly stopped. The sudden stop produces pressure spikes for both the motor and valve.

In trying to imagine what might have gone wrong with your valve, I wonder if the non motor spool together with load checks might have not been a good combination.

Best to provide Princess with all the facts as they have technical resources from the manufacturers

Since a motor spool is mentioned as an option in the spec's for your existing valve you may not need a separate valve for the motor.

Dave M7040

Thank you, very much appreciated. :thumbsup:

ptsg · Jun 6, 2020

Don't forget that you also want the motor to be locked when the spool is in Neutral, so the rollers won't move on its own.

That setup doesn't put much load on the motor or valve when the spool moves to Neutral. IMO a regular spool will work just fine.

On my homemade backhoe, I have a hydraulic motor for the drive connected with a simple valve. That thing handles all the digging forces and driving momentum on the motor and valve. It's been like that for over 800 hours without a single problem.

Dave M7040 · Jun 6, 2020

ptsg said:
Don't forget that you also want the motor to be locked when the spool is in Neutral, so the rollers won't move on its own.

That setup doesn't put much load on the motor or valve when the spool moves to Neutral. IMO a regular spool will work just fine.

On my homemade backhoe, I have a hydraulic motor for the drive connected with a simple valve. That thing handles all the digging forces and driving momentum on the motor and valve. It's been like that for over 800 hours without a single problem.

Does your valve have load checks in it?

Dave M7040