WGP Karnivor HPR Overhaul

Today I’m cleaning and lubricating the high pressure regulator (HPR) on a Worr Game Products (WGP) Karnivor Autococker. This one has been gathering dust for quite some time so I thought it best to service it before taking it to the field.

WGP Karnivor HPR

It’s pretty easy to remove the regulator from the marker. The hose unscrews readily enough from the elbow on the regulator. You can then easily unscrew the regulator.

To remove the valve seat you first need to remove the circlip on the bottom of the regulator. Then you can unscrew and remove the adjusting screw using a hex wrench. Next tap the regulator body against a wooden block to dislodge the valve seat and the seat spring. There is also a brass stem guide and o-ring behind the valve seat that isn’t shown in the photos. This may drop out or can be pushed out with an o-ring pick once the regulator piston has been removed.

For the next part of the disassembly you need to separate the two halves of the regulator. I usually grip the top of the regulator in a vice using two blocks of wood I’ve cut to fit before removing the lower section by hand. Now you can tap the top of the regulator against a block of wood to remove the regulator piston and belleville spring stack.

Now check the valve seat and o-rings and replace if damaged (the valve seat should rarely need replacing). Then clean, lube and reassemble. It’s as simple as that. One tip for reassembly is to use a small hex key or rod to place the stem guide, its o-ring and the seat spring and to guide the regulator piston stem through the stem guide.