If we look at it as two main parts inside one case, we would have an electric motor and a pump sitting next to each other.
It's possible to have an electric motor that runs okay, and a pump with it's rotor/gerotor star etc either broken or no longer attached to the shaft.
In that kind of scenario the motor shaft spins happily along without any load, and the pump won't operate until physically jarred or bumped a certain
way that allows the pump rotor to grab. When it grabs, it makes fuel pressure.
Not saying that's the issue, I have no idea, but depending how it's built it's a possibility the pothole knocked the rotor loose.
Interesting. I may take a stab at taking this pump apart and having a look. Just seems like too much of a coincidence that my issues started after that bang.
I believe those pumps are designed to run without a return type regulator. I have the HP150 without a return and have never had any issues.
When it stops pumping does the pump sound like it's unloaded? The pump should sound different when it picks up fuel and builds pressure.
The 125 doesn't require a regulator per Holley, but I added a return line because last year I was having horrible vapor lock issues, probably because of the routing of my lines which are now wrapped in heat shield.
The pump sounds were pretty erratic, when pumping, it didn't sound much different than when there was zero pressure.
