Hello everyone!
Just want to let it be known to all that I am strictly a novice
but will do my best to make some sort of sense in relating my electrical problem to you. I have a 1982 Ford E350 Econoline chasis under a 23' motorhome with dual feul tanks and a 460 CID engine and all the normal extras such as automatic transmission, A/C, electric wipers, power steering/brakes, etc. The VIN number is IFDKE30L5DHA91338. Now, here is my problem. I found that when the motor sat unstarted for a legnthy period of time I would have to really grind on the starter in order for the intank electric fuel pump to boost gas up to the carburator. Thinking that I could cut down on the starter working time to start the engine from a cold start, I installed an on-off-on rocker switch and hooked it straight into the electric wires that service the two fuel pumps. I can now depress the side of the rocker switch that relates to the appropriate gas tank which in turn prepumps the carburator full before trying to start the engine. It works fine. very short starter use now. Recently I found that the engine stops running after it used the gasoline in the carburator. Same story when I toggle over to the other tank. Seems like the fuel pumps are not getting any electric current when I turn the ignition switch on and try to start the engine. All the fuses are ok. Could I possibly have a short or bad connection somewhere between the ignition swith and the fuel tanks? HELP! HELP! HELP!
Mendi1

 

Welcome to FTE!

Can we make this a Non-Poll type thread please ?

 

If you have an in tank electric pump, then why are you grinding the starte? Just turn key on for a couple of seconds to let the pump prime, or you could run a second primer pump on it's own. I think your eletrical problem may come from the switch and splice pulling amps, or low current causing your pump to stumble. If you need to prime it, then get a small inline pump, and run it off it's own power source. It will pull fuel thru the original pump.

Oh, and I voted smiles, just kidding

 

hi,there......I've got a VERY similar vehicle,and just finished FULLY re-wiring it after an engine fire.--First,the pumps should be powered by two separate systems...In the pre start ,a pump is powered through the starter relay.When the engine is running,there is a relay activated by oil pressure--you should see a relay in the same place as the oil pressure guage sender at the top/rear of engine-there are two wires coming off this-use a simple test light to see if there is current coming through this when the engine is running,and then where it stops.
X-i's post above is a good idea-works fine even if tank pump doesn't work at all.

 

Here's an old thread.

https://www.ford-trucks.com/forums/s...hreadid=207783

 

Thanks to all for your quick response to my question. However, I failed to include in my original message that when I turn the key on and start the engine and while holding the rocker switch in for the selected tank the engine will start and run as long as I hold the rocker switch in. When I release the rocker switch the engine will run until it uses the gasoline that is in the carburator then stops running. Ditto when I toggle over to the other tank and hold the rocker switch in. Hope this added info might be of some help in your diagnosis of this problem.

Mendi1

 

OK from the way I read it....you installed a switch that powers the pumps when pressed and when you release the switch the carb runs out of fuel and dies because the pump isnt running..........so did you run a hot lead to the off side of the new switch that is powered when the key is in start or run?????
If not then the fuel pump will only run when the switch is held to on.
If you did run a wire there then I can only "assume" it isnt getting power on it from the ignition switch....since the pumps run fine with the toggle switch.
Fuse???? Bad wire????? Igniton switch?????

 

Thanks Sparky!
I gather from what you are suggesting that there has to be a lost connection somewhere between the ignition switch and the wires that service the fuel pumps. I'll check out this circuit. The odd thing about this problem is that everything has been working fine from day one. "Greasymonkey" above mentioned maybe a bad relay at the pressure gauge sending unit. I'll check this also.
Will keep everyone informed as to the outcome if it gets corrected.

Mendi1