Help I lost

[californiastage]

I have a Northman Fluid Power Hydraulic Directional Control Valve 19.8 GPM, 4500 PSI, 3-Position, Double Solenoid, Tandem Center Spool, 12 Volt DC Solenoids, Model# SWH-G03-C6-D12-10
at fist glance seems to be working fine, how ever I noticed when I had a load on the cylinders 500 -600 lbs. that (shown on line gage) that when you would release to let load down that it would continue on its own with no power to the solenoid. Remove the load and it would stop as it should.
Also I noticed a slam sound in the hydraulics when releasing.

 

[kennyd]

Welcome to TBN

I am looking the the specs for that valve..It is THIS ONE correct?

Nothing is jumping out at me as being wrong...Possibly some dirt got in it and the spool can't self center all the way

 

[californiastage]

Yes thats the one, however I got things working very well now, I installed a check valve that meter in one direction tha actualy linits the sudden impact of the release alowing the valve the center quite easly. We had other aplication that we exseiancing the same thing and we install the valves there and it works extreemly well. We are very happy FOR NOW!
Thanks Dave

 

[J_J]

Your plunger in the solenoid is sticking.

When you apply power, that solenoid causes that plunger to operate fairly fast. There should be no delay between the time you hit the switch, and the solenoid actuating. If it doesn't, you might have had some Teflon pieces, or some crud causing the plunger too stick. You should hear the valve actuate, and if you want to hear it better, put a screw driver on the solenoid, and put the plastic handle to your ear. It will transmit sound quite well. Fluid going through a solenoid valve, is either full on or off, whereas a manual valve has a sliding spool, sliding past an internal port.