Outdoor Power Equipment and Small Engines - Can't remove pump - Excell pressure washer

I have an EXHA2425 washer and the pump has failed. Prior to ordering an upgrade replacement, I want to remove the old pump and inspect the motor shaft. Per the instructions, I have removed the fittings, the unloader valve and have disconnected the pulse hose. The four mounting bolts have been removed. The pump seems to be stuck on the shaft. I can rotate the pump on the shaft a few degrees right & left, but I can't pull it off. Is it likely that I have corrosion to the extent that the pump won't slide off of what I assume is a drive gear?

Once the pump mounting bolts going to the engine are removed, the pump should pull off the crankshaft. If not, corrosion is the likely cause. I have had one or two very stubborn ones...and one I had to cut off (oxy-acetylene torch...cut the pump coupling away from the crankshaft).

Thanks for your help cheese. Unfortunately, I don't have a gas-fired wrench. I could try a recip with a metal blade. If I didn't live in the sticks without a repair shop around, I would take it in and let someone else have the honor of removing the pump.

An impact hammer usually drives stuck stuff off shafts, I'd try that before cutting.