Troubleshooting Cat 66DX Water Pump

[wcodyd]

Hello,

I have a CAT 66DX 4,000 PSI 4GPM water pump. It is constantly releasing water on the relief valve, rather or not the trigger is depressed. Oddly, when I connect a pressure gauge to the high pressure side, the pressure will read 5,000 PSI.

Is this a problem with the unloaded or the valves? I’m trying to determine what I may need to replace.

Thank you!

 

[water guy]

Really?

 

[Greg Pack]

Hopefully this is a simple adjustment needed. Turn the black knob counterclockwise until the pressure gauge drops to the advertised output pressure on the unit. If it doesn't drop low enough you may have a bad regulator which needs to be replaced. Good luck!