CAT Pump no pressure

Hi all, new here and was wondering if someone might be able to show me something I missed.

So I purchased from craigslist a Northstar hot water unit, which is an older version of this NorthStar Electric Wet Steam & Hot Water Pressure Washer — 2700 PSI, 2.5 GPM, 230 Volt | Electric-Hot Water| Northern Tool + Equipment

I changed out the electric motor Leeson High-Pressure Washer Electric Motor — 5 HP, 3450 RPM, Model# 116709.00 | Electric Motors| Northern Tool + Equipment

and the pump CAT Pump Pressure Washer Pump — 2.5 GPM, 2750 PSI, 5 HP to 6.5 HP Required, Model# 3DNX25GSI | Pressure Washer Pumps| Northern Tool + Equipment

powered by my generator or the house plug in, the motor works, but the pump isn't building pressure.

I have tried the owner's manual and other troubleshooting tips, nothing is working.

Any more information needed I will be happy to provide, and thank you in advance.

Our Sponsors