Hey Hambers, I'll try my best to describe what i'm trying to achieve. Car/Engine: 235 Chev: Has any one installed an Electric Fuel Pump, But Kept the Original Fuel Pump, in Place on the Motor, for Aesthetics? (Instead of using a block off plate) I'm planning to remove the Plunger Arm from the Mechanical Fuel Pump, in the hopes to pump THROUGH the original Fuel Pump using a Electric Pump. That way, the engine bay still looks somewhat original of that time period. I'm not sure if the Electric Pump will be able to push through it with enough PSI and GPH to keep up with the Dual Carburetors. (I'll be purchasing the Holley Mighty Mite Electric Fuel Pump 1.5-4PSI/28 GPH) There are threads regarding Elec V's Mech but this thread isn't about that... Appreciate any and all Feedback and information. Cheers!
an electric pump will push fuel through the mechanical pump just fine. You don't need to disable the mechanical pump for that to happen, either. The pump has inlet and outlet check valves, and if there is fuel pressure, the diaphragm doesn't move anyways. But you really should take apart a pump so you can see how it works. As well as read the old shop manual that explains it. http://chevy.oldcarmanualproject.com/shop/1954truck/54ctsm0667.html .
^^^^^ What about diaphragm going bad after sometime (when???) then leaking either externally or worse, internally. I'm the type that would open things up and create a straight internal byp***.
Run the electric thru a fuel block to the carbs and run a fake line from mech. fuel pump to fuel block. Seems like a lot of trouble to look traditional anyway you do it. Who would notice if mech. pump was gone?
crcooper.. a stock GMC 228 fuel pump with 1/4” pipe fittings will keep up with a 302 with 3 holleys, what are you worried about. I had many many 235’s with multiple carbs and never used an electric fuel pump. If your worried, drill out the fittings bigger and use a 5/16” line to the carbs and feed the pump with a 3/8” line... that will be good for 500 hp.
Even better then. Ever try to fool someone that something is lesser or not able to keep up at the street races (not what the news calls street racing these days)?
Hey guys, thanks for your input. Really appreciate it. I understand the Mechanical Pump will keep up with 2 carburetors, no problem. Long story short....2 brand new Mechanical Fuel Pumps out of the box, with an inline fuel pressure gauge fitted (That i have checked as well) and i cant get any more than 1-PSI....Electric it is. This Thread isn't about the age old debate of Mech V's Electric.... Yes its completely unnecessary to even to be thinking about this. Its not an emergency, its not important in the slightest....but why not think about it? Certainly not breaking the bank, nor harming anyone. Without asking questions, you will never know, right? I had concerns of petrol leaking past the Diaphragm (Now and in the future) so i do think of removing the Diaphragm completely, and Lazer cutting a "Blanking Plate" + Gaskets, and install in its place. Just asking the question..... If you think its ridiculous, that's ok! i'll still ask the question though
Looking at the engine I would think a fuel block would look cool on the firewall. I don't even see the fuel pump in that picture. lol
Sounds like stock that's been sitting on the shelf for a long long time and diaphragm has dry rotted. Happens here in the states a lot since fewer and fewer car have carburetors these day's.
Thanks Johnny Gee. I have read few comments of guys buying numerous pumps, which all have failed diaphragms (whether theres something else at play here, or not, is another story), but its comforting to know it is a well know problem, even in the states. Crawling home from a Car Show at 25-30mph is not fun Hung Over!
Before doing the swap. Have you made sure that everything from the tank to the pump is flowing as it should be? Another simple fuel pump pressure test with inlet line at fuel pump disconnected may have a surprising finding.
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