This is still a risky way to run a fuel pump. What stops the fuel pump running if the engine stalls etc?...With your set up any time the key is sending power to the coil your fuel pump will be running. A better way is to wire the pump via a 3 terminal oil pressure switch, as explained by theoutlaw2395's reply below. You can also trigger the fuel pump relay from the alternator, if you have an alternator with a charge warning lamp (L) terminal. Connect a wire and a diode with it's silver line pointing towards the fuel pump relay coil+ terminal (86) tapped into the alternaltor charge lamp terminal (L) to turn the relay on once the alternator starts charging. The fuel pump will only run once engine is running and alternator is charging, so if the belt ever breaks or engine stops spinning the alternator, the pump also stops.
I'm using an oil pressure switch w/the pump relay. I'd say put the coil lead on the NO of the oil pressure switch, tap a lead off the starter to the NC, and the pump relay lead to the C of the pressure switch. Going to start (power from NC to C) shifts the fuel pump relay powering the fuel pump, as oil pressure builds (about 4 psi) the oil pressure switch will shift to the NO post and take over powering the fuel pump relay. As Simon Ilett pointed out about stalling, should the engine stall, the oil pressure switch will shift (as loss of oil pressure) to the NC contact, (but that's a dead post until the ignition is moved to START again) and the fuel pump relay will be depowered shutting off the fuel pump.
The only problem with using the coil to run and accessory is that your taking or using amperage from your coil and essentially taking amperage away or effecting amperage from the spark plugs. I have done things like this in the past but now leave the coil alone to do its job to it's potential and source power directly from the battery or accessory tab on fuse block. This is what using a relay is all about
I used 16 gauge for the wire going to the relay off of the coil, and 12 gauge going to the pump. It was probably overkill though. Just make sure you’re fuse protected
electric fuel pump, does it really correct a fuel boil issue ? '68 slant six does has boil issue during summer months not in winter months. i'm gonna have to look into it, been wanting to install electrical pump cause of prime 👍
I have the same problem with my 2.8 l V6 With the high altitude and high temperatures where I live, I found that it helps immensely to run premium fuel (less ethanol) in the summer, insulate my fuel lines and move them away from the exhaust manifold, in addition to putting vents in my hood and running the radiator fan between stop's when running errands in town on the blacktop. I have also found that on Long stretches of road that are 25 or 35 miles per hour I keep it in second gear to keep the RPM's up, lower RPM's meanings lower fuel pressure with a mechanical fuel pump so I've learned.
i run mine off the fuse panel controled by the switch but i also use or run my wire through a oil pressure switch,if the motor stops running it cuts off the fuel pump,this is done oem style
I wasted hours watching all kinds of bs this was the one I needed lol thanks a ton
This is still a risky way to run a fuel pump. What stops the fuel pump running if the engine stalls etc?...With your set up any time the key is sending power to the coil your fuel pump will be running.
A better way is to wire the pump via a 3 terminal oil pressure switch, as explained by theoutlaw2395's reply below.
You can also trigger the fuel pump relay from the alternator, if you have an alternator with a charge warning lamp (L) terminal.
Connect a wire and a diode with it's silver line pointing towards the fuel pump relay coil+ terminal (86) tapped into the alternaltor charge lamp terminal (L) to turn the relay on once the alternator starts charging.
The fuel pump will only run once engine is running and alternator is charging, so if the belt ever breaks or engine stops spinning the alternator, the pump also stops.
I'm using an oil pressure switch w/the pump relay. I'd say put the coil lead on the NO of the oil pressure switch, tap a lead off the starter to the NC, and the pump relay lead to the C of the pressure switch. Going to start (power from NC to C) shifts the fuel pump relay powering the fuel pump, as oil pressure builds (about 4 psi) the oil pressure switch will shift to the NO post and take over powering the fuel pump relay. As Simon Ilett pointed out about stalling, should the engine stall, the oil pressure switch will shift (as loss of oil pressure) to the NC contact, (but that's a dead post until the ignition is moved to START again) and the fuel pump relay will be depowered shutting off the fuel pump.
Thank you, It saved me from probably catching on fire! Lol
The only problem with using the coil to run and accessory is that your taking or using amperage from your coil and essentially taking amperage away or effecting amperage from the spark plugs. I have done things like this in the past but now leave the coil alone to do its job to it's potential and source power directly from the battery or accessory tab on fuse block. This is what using a relay is all about
What size of fuse did you put on the trigger wire
Only question I have is did you use the same gauge wire throughout your system or did you have to get a little thicker on the fuel pump side
I used 16 gauge for the wire going to the relay off of the coil, and 12 gauge going to the pump. It was probably overkill though. Just make sure you’re fuse protected
@@oldmuscle8156 thanks!
Hi I was just wondering what amp power fuse to use is it a 10 amp
usually they recommend 20amp
electric fuel pump, does it really correct a fuel boil issue ? '68 slant six does has boil issue during summer months not in winter months. i'm gonna have to look into it, been wanting to install electrical pump cause of prime 👍
Run a return line to tank or return style filter.
@@joshuaphillips1867 Thanx Bro' 👍
I have the same problem with my 2.8 l V6
With the high altitude and high temperatures where I live, I found that it helps immensely to run premium fuel (less ethanol) in the summer, insulate my fuel lines and move them away from the exhaust manifold, in addition to putting vents in my hood and running the radiator fan between stop's when running errands in town on the blacktop. I have also found that on Long stretches of road that are 25 or 35 miles per hour I keep it in second gear to keep the RPM's up, lower RPM's meanings lower fuel pressure with a mechanical fuel pump so I've learned.
WHAT? CONFUSING AS HELL!!!
You very confusing sorry I have to say that
i run mine off the fuse panel controled by the switch but i also use or run my wire through a oil pressure switch,if the motor stops running it cuts off the fuel pump,this is done oem style