Electric fuel pump

[Asgeir]

Hello, Im thinking switching to a electric fuel pump to help stop vapor lock after the engine runs. Currently have a mechanical three port one and once the engine gets warmed up and you shut if off to like get gas, I have to crank, crank, crank to get it started. I looked and read some forums that the little red or black electric edelbrocks are like a 50/50 (they work or dont). I just wanted to see what experience yall have and ran with? I would love to do the 87 tank swap with the pump in the tank but I currently dont have that $$, just got the transmission rebuilt. She has a fresh 383 build and a Holley 750 CFM carb.

 

[dd1990]

Never had much luck with those external electric pumps...I think electric pumps need to be in the tank so the gasoline cools it, that's why oem electric in tank pumps work. Is your fuel return line still connected and free flowing back to tank?

 

[AuroraGirl]

you need a pump near the tank that also doesnt have a check valve, since you need it to function with your mechanical pump most of the time, a check valve would block it from pulling fuel. so installed near the tank gives it the best life span since it doesnt have to pull a very long column of fuel and should still have some prime to it while your truck is hot and bothered


Then you wire it to a switch or you put it on a timed relay of sorts so you can run it long enough to reduce the issue

On my dads 95 tbi , it has a hot fuel module, and it runs upward 8 seconds to prime the fuel pump iirc, so if you needed an idea for how long thats how much his tbi (15 psi?) uses from its in tank pump

 

[Asgeir]

Never had much luck with those external electric pumps...I think electric pumps need to be in the tank so the gasoline cools it, that's why oem electric in tank pumps work. Is your fuel return line still connected and free flowing back to tank?

I dont know, havent drop the tanks. I know the tank selector doesnt work and I will be working my way back. I want to say yes, once I drop the trans to replace it with the new one, I will look and see if the line is at least running back there.

 

[Bextreme04]

Hello, Im thinking switching to a electric fuel pump to help stop vapor lock after the engine runs. Currently have a mechanical three port one and once the engine gets warmed up and you shut if off to like get gas, I have to crank, crank, crank to get it started. I looked and read some forums that the little red or black electric edelbrocks are like a 50/50 (they work or dont). I just wanted to see what experience yall have and ran with? I would love to do the 87 tank swap with the pump in the tank but I currently dont have that $$, just got the transmission rebuilt. She has a fresh 383 build and a Holley 750 CFM carb.

It's unlikely that you are actually getting vapor lock with the symptoms you are reporting and the equipment you have. If it was vapor lock you would get an immediate start and then it would die after a few seconds once the fuel bowl ran out. There are a few things that could be causing your issue, but I would first be looking at making sure the carb is fully dialed in right. Hard hot starts are usually caused by flooding, will is start after a few cranks if you put the pedal to the floor and hold it while cranking under the same circumstances?

Make sure you have the float bowls height set correctly and the idle mix screws adjusted properly for a lean idle setting. Then make sure timing is right and that both the regular hot idle and cold idle are set right. What kind of choke does it have? Electric? Is it working right?

 

[Asgeir]

It's unlikely that you are actually getting vapor lock with the symptoms you are reporting and the equipment you have. If it was vapor lock you would get an immediate start and then it would die after a few seconds once the fuel bowl ran out. There are a few things that could be causing your issue, but I would first be looking at making sure the carb is fully dialed in right. Hard hot starts are usually caused by flooding, will is start after a few cranks if you put the pedal to the floor and hold it while cranking under the same circumstances?

Make sure you have the float bowls height set correctly and the idle mix screws adjusted properly for a lean idle setting. Then make sure timing is right and that both the regular hot idle and cold idle are set right. What kind of choke does it have? Electric? Is it working right?

It doesnt have a choke, I have not idea about setting a carb, have a buddy that did it with the vaccum gauge. Down the road, I want to get the sniper II. I will set about seeing if any old timers around my area can help with that.

 

[Matt69olds]

Are you SURE the float level is correct? It needs to be just below the sight glass window, if you shake the truck fuel should just dribble out the window.

Once you’re sure that’s good, drive the truck until the engine is good and hot, then shut it off. Wait a few minutes, check the float level again. If it’s gone up, your hot restart issue isn’t vapor lock, it’s more than likely flooding.

You say the pump is a 3 port, is the return line actually functional? Too many people think you can just cap that line and go. The return line is designed with a tiny orifice in the pump, its purpose is basically a controlled internal leak. The leak constantly circulate fuel thru the lines, pump, and back to the tank. It also vents fuel back to the tank after a hot shutdown. Without the return point, the hot fuel in the lines and pump will expand, possibly to the point where it can push the float off the seat, dumping fuel into the intake.