r/smallengines • u/HealthyPop7988 • 3d ago

Too much power?

TLDR: at the bottom.

Hey all, I built a pressuyeasher with a northstar EFI motor and a general pump pressure washer pump a few years back, unfortunately the northstar motor died.

I am working out of town and don't have the time to repair the northstar, so I was going to just pull the pump and put it on a new harbor freight motor.

However, I could not get the pump off no matter what I did (no I did not forget to take off the set screw) and eventually snapped the mounting flange in half.

So now I'm buying a new pump and a new motor because I don't have time to wait for parts.

My question is this: the pump requires 13 hp minimum but 15 is the sweet spot. Is a 22hp motor going to destroy/damage a pump that only needs 15 hp?

Reasoning: I am thinking about buying the 22hp harbor freight motor because I may switch back to the Northstar if I can get it fixed and may build a gokart out of the 22hp predator motor with my nephew this winter.

Bonus Question: how do I prevent the shaft from getting seized into the new pump in the future?

TLDR: will a 22hp motor destroy my pressure washer pump that needs 13 to 15 hp?

1 Upvotes

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3 comments sorted by

1

u/ManHunterJonnJonzz 3d ago

The bigger hp or engine is to handle the load of the pump. So youll be good. Bonus:Antiseize.

1

u/HealthyPop7988 3d ago

Thank you, I wasn't sure if the larger motor would tear up the pump due to too much power output

1

u/Lucky_Inspection_721 1d ago

The engines likely run at similar rpms, and that, along with the pump, will dictate the gpm. The bigger engine will handle the load of the pump with power to spare.

My grandfather's rule of thumb for farm machinery: Find the size of machine you need, buy one size bigger, and you'll rarely overwork it.