Fuel Pressure Regulator and Pump Testing


Hayabusa Immortal
Hi there. I'm hoping someone has experience with the in-tank gen-1 pumps.

My pump is toast from tank rust. I found a new replacement on Amazon for $30. The fuel pressure regulator, however, has surface rust on it, so I'm sure if it'll be a problem.

Unfortunately, to get a new regulator requires getting a whole new filter assembly for $250+.

It's just a spring-loaded gasket, so it should be ok, right?


Also need to re-solder the connections and fuel level sensor. I'm guessing this is just a variable resistor, so I should be able to test if it works with an ohmmeter? :confused:

Yep, fuel gauge is a just a potentiometer, ohms test will be fine, as for the pressure reg, bolt it all up and test it, with a pressure gauge, on the outlet, once you have fuel in the tank, should be about 43 psi.
I was going to get a whole setup, but can't get in touch with the seller. Going back to fixing this.

I cleaned up the regulator, which has rust inside. This is the part that bugs me, since it isn't something that is sold separately. Fingers crossed it isn't compromised, otherwise I'm back to square one.

Getting some HCL to clean out the tank. Too many projects I haven't been able to focus my time on prepping the bike. The weather is nice, though, and I haven't ridden in almost five years, so that should help me shift my focus. :drool: