Service Bulletin HB-0930-08

Torque Specs for Hy-Brid Down Valve & Coil

When removing a down valve from a hydraulic pump for cleaning or replacement, the following installation procedure should be followed to prevent damage to the pump body or valve.

Be sure to clean the area around the valve so foreign material does not enter the pump body when the valve is removed. Remove the two wires to the down coil. Loosen the nut holding the coil to the valve and remove the coil. Using a suitable wrench, remove the valve from the pump body being certain that the screen remains on the valve. The screen can be removed from the valve for cleaning.

When installing the valve back into pump make sure the screen is seated properly and lubricate the o-rings on the valve. Finger tighten the valve and then torque to 150 inch pounds. This is very important as over tightening will cause damage to the valve and or pump body. Place the coil onto the valve shaft with the wire spade connectors towards the top and tighten the retaining nut to a value of 30 inch pounds. Over tightening the retaining nut will distort the down valve and may cause it to fail.

For more information on this or any other service bulletins, you may contact us directly.