Holmbury’s OCUKAC2318 is a high quality  pattern changing valve with a steel body and hardened spool for pilot applications, such as switching between John Deere and Cat control patterns on excavators.

Hanson Hydraulics Ltd. Blog article:

Extending the spool length and mounting the handle on the extended side allowed for flush mounting the valve on the underside of the floor plate. To modify the spool, a hole was drilled and tapped into the spool end(it’s a little tricky as it is a hardened spool), then an extension was machined to thread in. The extension was loctited in and cross drilled parallel to the original handle hole on the other end.This put the handle at one end of the spool, while leaving the limiting stops at the other end.

Check out the pictures below.  This valve is very compact and perfect for pattern changing applications. I would definitely use it again. Check out Holmbury Inc. http://www.holmburyusa.com/

Written for Hanson Hydraulics Ltd. Blog

Want a good seal for your PVG32 actuator?

Hanson Hydraulics Ltd. Blog article:

PVG32 Actuator PVMD

Sauer Danfoss PVG32 PVMD actuators (used on Waratah Processors), have a u-cup sealing the actuator shaft to the housing. It has been my experience that this seal is not included in the PVM seal kit. Waratah has created a seal kit, however it has also been my experience that it contains the wrong u-cup. The u-cup required is a metric size. – 11mm x 17mm x 3mm which is hard to find. The u-cup supplied in Waratah seal kits I have found is 11/16 x 7/16 x 1/8, close but not close enough. They will start leaking in short time.

 Here is a repair to replace this hard to find u-cup with an oring.

removing the nut and shaft

 Remove the nut from the housing. The oring on the outside of this nut is a 21.2mm x 26 x 2.4 oring and in this application could be 70 durometer. Remove and inspect the shaft for wear or grooving.  Have a look inside the housing, older housings had a tendency to crack. Remove the u-cup with a pick, being careful not to score up the sealing area.  Once the seal is removed, insert a blind hole bearing puller and expand into the groove, making sure that the tool will not gouge up the seal area.  Press on the tool to press the busing out the bottom of the nut.

PVMD parts

Tool assy for pressing the bushing out of the nut

Pressing the bushing out of the nut

Machine .075” off the face of the seal side of the bushing (not the shouldered side). This creates a seal groove .190” tall, perfect for a 2 series oring (205) 70 durometer. Press the bushing back in, pop in your oring, install the shaft, tighten the nut back up and you’ve got an actuator/spool cover that should be leak free for a long time.

Nut, u-cup, Bushing

The orings that seal the face of the housing against the valve body are: 5mm x 9mm x 2mm

Written for Hanson Hydraulics Ltd. Blog