Added switch for elec fuel pump

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NAM VET
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Added switch for elec fuel pump

Post by NAM VET »

When my truck was up at Charles' shop a year ago, for making some things right I had done wrong, one of the things his shop did was to put in a 24v Facet "marine" fuel pump, puts out about 4 psi, has an integral and replaceable filter. But to lessen the risk of continued fuel pumping in case of an accident, he wired in a oil pressure switch which is set for I think about 5 psi of oil pressure. If I wreck, and the engine stops, in seconds the fuel pump is switched off. The pump has a by-pass when the starter is turning, to allow fuel pressure to build while the engine is cranking. In reading some of his old posts, he mentioned that sometimes he has installed a momentary on toggle switch, so the driver can pump fuel for a few seconds without having to wait for pressure to build with the starter turning.

So... I wired in a momentary on toggle switch, using an old hole in my dash, then ran fused wires to the 3 pole oil pressure switch, basically shorting the switch thru my toggle. I had not driven my truck in several weeks, being away, and my fuel will drain out of the clear plastic WIX fuel filter and lines when my truck is parked. So, when done, I held the toggle up for about 3 or 4 seconds, hearing the Facet pumping, and hit the starter. The truck stated instantly, there was no need to spin the starter for some seconds to get the fuel up and into the carb. I was surprised to find my truck immediately fired, and then settled into a nice even idle, without even having to slightly blip the throttle to clear the carb. No choke.

It may have been helped by the near 100 degree temps, and in the winter the carb may have needed a moment of choke. Pegasus Auto Racing has the 24 V Facets, if you are interested. Now, no need to wait for the oil pressure to build and bypass the pressure sensor. Here is a pic. By the way, Charles also installed a coolant filter, visible. You can see my mechanical oil pressure line to my AutoMeter oil pressure gage on my steering column. I crimped and soldered all connections.
hc
[url=https://postimg.cc/HrYH2zkd][img]h ... .jpg[/img][/url]

Be safe out there.... HC?
T. Highway
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Re: Added switch for elec fuel pump

Post by T. Highway »

Very nice setup and thanks for sharing the details Hal.

Bert
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sturmtyger380
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Re: Added switch for elec fuel pump

Post by sturmtyger380 »

Is the copper line going to an oil pressure gauge?
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NAM VET
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Re: Added switch for elec fuel pump

Post by NAM VET »

yes, the copper line, covered in tubing, goes to my Autometer oil pressure gage on the steering column. Much easier to see precisely what my oil pressure is, and how fast it rises. And I have given up on trying to run a separate line to my Fact fuel filter, tried several ways, but I can't come up with to switches to the pump that won't short out one or the other lines. So will just let the functional pressure kill wires do what they do. No pre-fueling that I can make work. HC
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