Re: 1950 Custom 8 Electric Fuel Pump

Posted by Fish'n Jim On 2022/8/21 14:34:45

It depends.
This is the current best practice I could find.
If the "e" pump is self/internal pressure regulating to <6 psig, then you can wire in a relay off the ignition hot lead and install a branched pressure switch, keep original, that accepts another switch to feed back to the relay that shuts it off when motors off = no oil pressure.
The "how to" info is on the airtex pump site and comes with the pump. The relay powers the pump only when the key is on, and the pump shuts off when pressure is good. Power is off when the key if off. I ran a separate resettable breaker for the 12V pump feed.
I put this in on the Cad last year after fighting bad mechanicals coming in from MX. They moved the factory down there a few years ago and changed design and have/had issues. I notified airtex, but not sure where it is now.
As best as I could tell there was only one model like this for carbs. And it's louder than I'd like. I haven't got around to noise isolation.
ps: that's part of the problem with asking for advice on the internet, etc. and not properly diagnosing the fault.
But not all for naught.
A good running mechanical will do the job just as well. They ran like that for decades as produced.