Electric fuel pump wiring

mmudge

True Classic
As some of you may know, I removed my FI from my '81 and went back to a DAT34. It's coming along and was running nicely. Then my fuel pump failed. When I installed the one that went bad I'd lost fuel pressure. So I installed a new one. Now I have pressure all the way to the carb (or at least the line fills) but nothing in the fuel bowl. Now I'm wondering if I messed up the wiring, but I don't know where. I can't find a wiring diagram for it but there are some green, grn/blk wires down by the pump. Can someone help me sort this out? Currently I'm running a hot wire from the coil B+ and ground to the chassis.

Thank you

Mudge
 
Undo the hose from the carb and turn on the ignition. If gas comes out, your pump is wired OK...if no gas you have a problem. If you have good fuel flow from the pump but the float bowl is still empty then you have a blockage between the pump and the inside of the carb.
 
Would using the lg FI filter cause a problem? Perhaps the 4 psi isn't enough to push thru that large a filter? Also I hear a burbling sound coming from the gas tank. Reverse polarity or just the return line?
 
I don't think the filter would cause that much of an issue. The "burbling" is definitely strange, I would entertain the idea of it being reversed. If anything switch and see what happens.
 
Undo the hose from the carb and turn on the ignition. If gas comes out, your pump is wired OK...if no gas you have a problem. If you have good fuel flow from the pump but the float bowl is still empty then you have a blockage between the pump and the inside of the carb.

Carl If the electro solenoid is bad would that keep the bowl from filling?
 
Greetings, at the risk of hijacking the thread, I am considering adding an electric Facet fuel pump to my carb' X. Does anyone have a recommendation where to connect the wiring? Which fuse/run wiring directly tp the fuse panel/is there an alternative power supply within the engine bay?

Thank you.
 
Carl If the electro solenoid is bad would that keep the bowl from filling?
If you mean the idle solenoid, no it does not affect bowl filling. The only thing that controls bowl filling with fuel is the float which rises with the fuel level and shuts off fuel flow when the fuel gets to the proper level. The float needs to be set correctly and make sure the float valve is functioning properly. This is set forth in the manual. I suppose if the float valve is stuck or the float is set too low it would shut off fuel flow or severely limit it.
 
Greetings, at the risk of hijacking the thread, I am considering adding an electric Facet fuel pump to my carb' X. Does anyone have a recommendation where to connect the wiring? Which fuse/run wiring directly tp the fuse panel/is there an alternative power supply within the engine bay?

Thank you.

Check here:

https://xwebforums.com/forum/index.php?threads/fuel-issue.31925/#post-269130

It does not tell you which circuit to use, but it does identify critical issues, such as how to have the pump shut off if there is a crash and the ignition is still on.

Paul
 
Which Facet fuel pump? They make several.

The most common is the small rectangular unit with pulsed fuel delivery, These are low cost, work OK. The produce fuel to the carb in pulsed burst which can cause problems by essentially bouncing the float valve due to the pulsed fuel delivery. Put enough hose or fuel container after this pump to smooth out these pulses. Fuel pressure delivered not always predictable No a a favored pump.

Facet also makes a cylindrical ticker pump with a strainer built in on the bottom. These began life as a Bendix pump, eventually the design was sold and still made by Facet. There are several version from low pressure about 2-3 psi, 12Volts nominal which is the one to use a higher variants that produce fuel pressure above 4 psi and 24 volt variants used in small piston engine aircraft and boats. Favor this pump as has a proven record of reliability and durability in cars, small aircraft and boats.

Carter makes a rotary vane fuel pump, these work good too. They tend to have smooth fuel delivery with minimal pulses. This pump requires a pressure regulator as the spec pump pressure is 4 psi and up.

In all cases do add an inertia switch to stop fuel flow in case of a crash. There are a number of them available, we used a OEM FORD inertia switch.
https://www.ebay.com/itm/Ford-Inert...ash=item1c93db53ea:g:kJUAAOSwtGlZMkNy&vxp=mtr

As for powering the pump, depends on the specific year of exxe. Basically it should be ignition switch power in the running position. Do add it's own fuse rather than stealing power from another circuit. This allows diagnostics to be done and reduces wiring confusion in many ways.

Do add a fuel filter post fuel pump. Adding a fuel pressure regulator with fuel return is a good thing.


Bernice





Greetings, at the risk of hijacking the thread, I am considering adding an electric Facet fuel pump to my carb' X. Does anyone have a recommendation where to connect the wiring? Which fuse/run wiring directly tp the fuse panel/is there an alternative power supply within the engine bay?

Thank you.
 
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