martin53 Posted May 7, 2018 Report Share Posted May 7, 2018 Look for help on how to wire a electric fuel pump. Is it necessary to hook it up to a relay or could I just run it to a switch and a fuse. Thanks Quote Link to comment Share on other sites More sharing options...
DonaldSmith Posted May 7, 2018 Report Share Posted May 7, 2018 You don't need a relay. I got fancy, in wiring my electric fuel pump. From McMaster Carr, I bought a double throw switch , constant on in one direction and momentary in the other. Push down and hold, to prime the carb. If the mechanical pump fails or falters, push up to have the electric pump turn on and stay on. Then I got worrying. What if I get in an accident and the engine stops but the electric pump is still on? So I bought an oil pressure switch. Engine running, pump on. Engine not running, pump off. But, like I said, I got fancy. Quote Link to comment Share on other sites More sharing options...
1949 Wraith Posted May 7, 2018 Report Share Posted May 7, 2018 A fused power and switch will work fine. Pushing the fuel from a location near the tank with an additional clear fuel filter before the pump is not a bad idea, as you are already cutting the fuel line. Quote Link to comment Share on other sites More sharing options...
Oldguy48 Posted May 7, 2018 Report Share Posted May 7, 2018 (edited) You might want to consider installing a "Ford Inertia Switch" in your fuel pump circuit. The switch "opens" if a severe enough impact is encountered, and disables the fuel pump. I wired mine in the power feed to my fuel pump. My fuel pump only draws a couple of amps (12 volt), so I didn't incorporate a relay. You can find them at your local "Pick & Pull" in Ford Explorers, Rangers, etc. behind the passenger side kick panel. If the switch should ever "trip", there is a reset button to restore operation. I've never had a "nuisance trip" with mine, and it provides an extra safety factor in the event of a collision. Edited May 7, 2018 by Oldguy48 Quote Link to comment Share on other sites More sharing options...
DonaldSmith Posted May 7, 2018 Report Share Posted May 7, 2018 About 18 years ago, I was about to go to work. My wife had left already. Suddenly feeling tired, I decided to sit in the easy chair for a while. Shortly thereafter, my daughter called from a nearby expressway, on a borrowed cell phone. Her car had been bumped lightly, and she had pulled over to the shoulder. The car would not now start. I knew the problem. I drove over to her location, opened the trunk of her Sable, and reset the inertia switch. Then my daughter and infant grand daughter were on their way. If I hadn' been known about the inertia switch, and had not grown tired so suddenly, my daughter would have had quite a time getting roadside assistance. And how many tow truck drivers would just reset the inertia switch instead of doing a tow and repair job? Quote Link to comment Share on other sites More sharing options...
martin53 Posted May 7, 2018 Author Report Share Posted May 7, 2018 3 hours ago, DonaldSmith said: You don't need a relay. I got fancy, in wiring my electric fuel pump. From McMaster Carr, I bought a double throw switch , constant on in one direction and momentary in the other. Push down and hold, to prime the carb. If the mechanical pump fails or falters, push up to have the electric pump turn on and stay on. Then I got worrying. What if I get in an accident and the engine stops but the electric pump is still on? So I bought an oil pressure switch. Engine running, pump on. Engine not running, pump off. But, like I said, I got fancy. Would you happen to have a diagram of how you wired it up. Im thinking of going this route. Quote Link to comment Share on other sites More sharing options...
martin53 Posted May 7, 2018 Author Report Share Posted May 7, 2018 2 hours ago, Oldguy48 said: You might want to consider installing a "Ford Inertia Switch" in your fuel pump circuit. The switch "opens" if a severe enough impact is encountered, and disables the fuel pump. I wired mine in the power feed to my fuel pump. My fuel pump only draws a couple of amps (12 volt), so I didn't incorporate a relay. You can find them at your local "Pick & Pull" in Ford Explorers, Rangers, etc. behind the passenger side kick panel. If the switch should ever "trip", there is a reset button to restore operation. I've never had a "nuisance trip" with mine, and it provides an extra safety factor in the event of a collision. This is a really good idea. I never thought about using a inertia switch. I'm really need a diagram of how to do it. Quote Link to comment Share on other sites More sharing options...
Oldguy48 Posted May 7, 2018 Report Share Posted May 7, 2018 When I got mine from the "Pick & Pull", I clipped off the wires/connector attached to it, and used the Pink, and the Green/yellow tracer wires which maintains continuity unless the inertia switch trips. I'm not sure if all those inertia switches are identical, but you can check for continuity with an ohmmeter or a test light. Quote Link to comment Share on other sites More sharing options...
DonaldSmith Posted May 7, 2018 Report Share Posted May 7, 2018 OK martin 53, here's a sketch of my fuel pump wiring. The switch is double throw, center off, with one throw constant on , and the other one intermittent, providing power while the toggle is held in position. The common post of the switch feeds the pump. For priming, hold the toggle in the intermittent position. For running the pump constantly, flip the switch the other way. Power for this position is controlled by the oil pressure switch. The N.O.position is closed only while the engine is running. Quote Link to comment Share on other sites More sharing options...
martin53 Posted May 7, 2018 Author Report Share Posted May 7, 2018 (edited) 1 hour ago, DonaldSmith said: OK martin 53, here's a sketch of my fuel pump wiring. The switch is double throw, center off, with one throw constant on , and the other one intermittent, providing power while the toggle is held in position. The common post of the switch feeds the pump. For priming, hold the toggle in the intermittent position. For running the pump constantly, flip the switch the other way. Power for this position is controlled by the oil pressure switch. The N.O.position is closed only while the engine is running. Thanks. This is very helpful. Is cb the fuse it runs through also where did you put the oil pressure switch. Edited May 7, 2018 by martin53 Quote Link to comment Share on other sites More sharing options...
DonaldSmith Posted May 8, 2018 Report Share Posted May 8, 2018 "CB" for "circuit breaker". It doesn't burn out and need to be replaced. The oil pressure switch screws into the block instead of one of the plugs along the oil gallery. It's the thing with the three yellow-insulated contacts. I installed it on an elbow and nipple, to be more accessible. Quote Link to comment Share on other sites More sharing options...
martin53 Posted May 10, 2018 Author Report Share Posted May 10, 2018 On 5/7/2018 at 5:58 AM, DonaldSmith said: You don't need a relay. I got fancy, in wiring my electric fuel pump. From McMaster Carr, I bought a double throw switch , constant on in one direction and momentary in the other. Push down and hold, to prime the carb. If the mechanical pump fails or falters, push up to have the electric pump turn on and stay on. Then I got worrying. What if I get in an accident and the engine stops but the electric pump is still on? So I bought an oil pressure switch. Engine running, pump on. Engine not running, pump off. But, like I said, I got fancy. I think Ill wire mine this way for now till I figure out a way to plumb the oil pressure switch on my hemi. Did you put the fuse before or after the throw switch. Is there any other way of getting a hold of you to ask more questions. Possibly Facebook messenger. My name is Martin Terrazas. Look me up please. Thanks 1 Quote Link to comment Share on other sites More sharing options...
maok Posted May 10, 2018 Report Share Posted May 10, 2018 28 minutes ago, martin53 said: I think Ill wire mine this way for now till I figure out a way to plumb the oil pressure switch on my hemi. Did you put the fuse before or after the throw switch. Is there any other way of getting a hold of you to ask more questions. Possibly Facebook messenger. My name is Martin Terrazas. Look me up please. Thanks It doesn't matter if the fuse is before or after, as long you have correct size fuse - 5 amp fuse should do the trick. Quote Link to comment Share on other sites More sharing options...
martin53 Posted May 11, 2018 Author Report Share Posted May 11, 2018 Just curious but will a 5-8 psi pump be to much for the 241 2 barrel carb. Also I was planning on bypassing the stock fuel pump and running just the electric pump. Thanks for the help everyone. Quote Link to comment Share on other sites More sharing options...
desoto1939 Posted May 13, 2018 Report Share Posted May 13, 2018 if you do not use the mechanical fuel pump then you might not need the toggle switch because the electric pump has to run all the time to feed fuel to the carb. So I would think if you have the electric FP wired to the hot side of the ignition switch then the pump will start as soon as you turn the key to the right to start the car. I would also think that by turning to the right and then waiting 10-30 seconds then the carb would be primed and the car would start. I would think about having a switch so that if the car was hit in an accident there is a way that the electric pump would automatically shut off so that the fuel would not be running into the carb when the ignition is on. You need an automatic kill mechanism in case of an accident or the car flips over. Just thinking out of the box. This is why I like keeping the mechanical pump as the primary pump and the electric pump as a back up and or priming pump. Rich Hartung Desoto1939@aol.com Quote Link to comment Share on other sites More sharing options...
DJ194950 Posted May 14, 2018 Report Share Posted May 14, 2018 Cannot say what PSI the fuel pump should run for your 2 bbl.carb. The repair manual will tell you for sure. The earlier 1 bbl's were only 3-3/12 psi and require a fuel pressure regulator in the fuel line to lower the pressure to within specs. Many older carbs ran at low psi fuel pressure, but yours?? Maybe somewhat has the appropriate repair manual if you do not currently have one, but suggest you do get one ? DJ Quote Link to comment Share on other sites More sharing options...
matt167 Posted May 14, 2018 Report Share Posted May 14, 2018 I have the Carter pump and no regulator on my '50 plymouth. I did not install it. It's under the hood but works fine. Noisy though Quote Link to comment Share on other sites More sharing options...
pflaming Posted May 14, 2018 Report Share Posted May 14, 2018 (edited) On 5/7/2018 at 6:06 PM, DonaldSmith said: The oil pressure switch screws into the block instead of one of the plugs along the oil gallery. It's the thing with the three yellow-insulated contacts. I installed it on an elbow and nipple, to be more accessible. I like this! What is your source for the switch. I will need two. I googled the switch and learned what, where, and how to install. Edited May 14, 2018 by pflaming Quote Link to comment Share on other sites More sharing options...
DonaldSmith Posted May 14, 2018 Report Share Posted May 14, 2018 (edited) Summit Racing, CRT-A68301, "Oil Pressure Safety Switch - Recommended When Wiring Electric Fuel Pump (Mfr. # A68301)" It cost me $17.97 plus shipping, back in July of 2015. I'll keep looking for the McMasterCarr double throw switch which I used. 7343K28 Toggle Switch, Sptd, on-Off-(on), 10 amps ($9.92 back in 2010) Edited May 14, 2018 by DonaldSmith tYpo Quote Link to comment Share on other sites More sharing options...
JD luxury liner Posted May 15, 2018 Report Share Posted May 15, 2018 I think the ford inetia switch from the local pick your part is simpler . only 3 wires, one is for an idiot light to let you know it tripped. total cost was about 8 bucks. Quote Link to comment Share on other sites More sharing options...
martin53 Posted May 15, 2018 Author Report Share Posted May 15, 2018 Well I got it running and sounded good then my car just died. Now the switch won't turn over the engine. I can get it running through the solenoid. Any suggestions. Anyone got a wiring diagram. Thanks for the help. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.