still2hi Posted April 20, 2004 Report Share Posted April 20, 2004 im having some problems and i cant seem to figure out why. its a 350 w/ 750 edlebrock carb and a electric fuel pump. when i get on it, after it shifts out of first and sometimes second it studders like it is starving for fuel. i have a regulator and gauge and for some reason my pump is only pumping 3 psi. when i shut off the pump and wait a min. air gets in the fuel line. you can see this through the clear fuel filter. when the car is running the gauge jumps anywhere from 2 to 4 pounds. my question is.. why is not holding a prime? is the pump only pumping 3 psi b/c it does not have a prime? and i was told that the fuel pump should be mounted by the tank(right now its up by engine) and thats why its not holding a prime? tia brandon Quote Link to comment Share on other sites More sharing options...
nurkvinny Posted April 20, 2004 Report Share Posted April 20, 2004 Pump should be mounted close to the tank. What do you have it regulated to? Should be around 6.5-7lbs. EDIT - just to be clear, I meant what did you try to set it to? Are you setting it higher than 3, but it falls to 3? Or is 3 all that you can get out of it? Quote Link to comment Share on other sites More sharing options...
still2hi Posted April 20, 2004 Author Report Share Posted April 20, 2004 when i first got the setup the regulator would allow me to go from 4 to 8 with the screw. now no matter what i put the screw at, it only will go up to 3. i put the air compresser up to it to make sure it isnt stuck or anything and it works fine. i have a holly regulator Quote Link to comment Share on other sites More sharing options...
nurkvinny Posted April 20, 2004 Report Share Posted April 20, 2004 What pump? Is it new? I have gotten (2) bad Holley 'blue' pumps from Jegs over the years. Also, what name-brand guage? I had a Jegs, water-filled guage take a shit in less than a month. Quote Link to comment Share on other sites More sharing options...
still2hi Posted April 20, 2004 Author Report Share Posted April 20, 2004 i bought the fuel pump about 6 months ago. its called street elecrtic fuel pump. part # p4070 but i couldnt find it on jegs website. i do have the water filled jegs gauge. Quote Link to comment Share on other sites More sharing options...
still2hi Posted April 20, 2004 Author Report Share Posted April 20, 2004 i just talked to my step-dad and he said he bought me the holley standard pressure regulator which only goes up to 4 psi. Quote Link to comment Share on other sites More sharing options...
desperado Posted April 20, 2004 Report Share Posted April 20, 2004 First, move the pump, it's meant to push and not pull fuel, it could be starving for fuel on the inlet side. Second, if you have a seperate fuel pressure /vacuum gauge, like the ones sold for tuning, hook it up to the outlet od the regulator and check the pressure. Then if it's not where it needs to be, disconnect the fuel line from the pump and test the output pressure of the pump. If it's a blue pump, it should be 9 to 11 psi. no less than 8 PSI. if that's not the case, either rebuild the pump of get a new one. If it came from Jegs, chances are once it saw fuel they will not swap it for a new one. If you can get them to great, if not and they will give you a rebuild kit that's cool to. They are not hard to rebuild, and if you like I can give you a hand with it. Other than that, save the pump for a spray kit, and go back to a mechanical pump. There are vrey good high flow high pressure mechanicals out there. NASCAR runs mechanical pumps and they are making around 800 HP, I doubt that you are making near that. Quote Link to comment Share on other sites More sharing options...
still2hi Posted April 20, 2004 Author Report Share Posted April 20, 2004 alright. ill see what happens when i mount the pump by the tank and see what i get. thanks for your input guys. Quote Link to comment Share on other sites More sharing options...
desperado Posted April 20, 2004 Report Share Posted April 20, 2004 not a problem. Vince and I are the carb kings, hell I didn't even know there was another car on CR that had a carb. smile.gif Quote Link to comment Share on other sites More sharing options...
still2hi Posted April 20, 2004 Author Report Share Posted April 20, 2004 lol, next time ill just ask you two.. desperado i also wanted to apologize for not calling back about the workbench. i was really looking for something with more metal and weld my own to fit in the garage right. didn't mean to leave you hanging on that. Quote Link to comment Share on other sites More sharing options...
nurkvinny Posted April 20, 2004 Report Share Posted April 20, 2004 Originally posted by still2high: i bought the fuel pump about 6 months ago. its called street elecrtic fuel pump. part # p4070 but i couldnt find it on jegs website. i do have the water filled jegs gauge. The 4070 (made by Carter, I think) runs at around 5-6 lbs, and doesn't require a regulator. I would move the pump near the tank, hook up the guage, and as long as you're not over 7lb, lose the regulator. Also, I wanted to ask how healthy the 350 is? I ask because a 750 is too much carb for stockish 350's... Quote Link to comment Share on other sites More sharing options...
still2hi Posted April 20, 2004 Author Report Share Posted April 20, 2004 its not a stock 350. i got the intake cam and carb as at kit. i have the performer rpm intake, 288 crane cam and its a brand new crate motor. the reason i put the regulator and gauge on was because i was getting gas in the oil. after i put that in, changed spark plugs to a hotter plug and got the timing alot better. i dont have that problem. now my next question is, if i go to 5 or 6 lbs wont that flood out the floats and cause them to stick. or will the carb handle that much gas. this is my first engine i have built and im only 20, so im still trying to learn as much as possible. Quote Link to comment Share on other sites More sharing options...
desperado Posted April 20, 2004 Report Share Posted April 20, 2004 Not to worry about the bench. As far as the fuel problem. 7 PSI is ok on that Edelbrock carb, but no more, and if you start seeing fuel running into the carb venturi at idle, then the pressure is too high. As far as the 750 thing, I would have to agree that even with what you have, a 750 is a bit big but being an Edelbrock air valve secondary then even with a tight convertor and mild performance build it's still ok. If it were a Holley, especially a double pumper it would be WAY too much. As far as it being your first motor, and I say this in all honesty, if it made *** first 20 minutes after fireup, you did fine. That's the finger crossed point, if it's not gonna stay together, it typically does it during break in. Congrats on the motor. And let me know if I can help out on anything. Quote Link to comment Share on other sites More sharing options...
KennyFKINPowerz Posted April 21, 2004 Report Share Posted April 21, 2004 Originally posted by NurkVinny: What pump? Is it new? I have gotten (2) bad Holley 'blue' pumps from Jegs over the years. Also, what name-brand guage? I had a Jegs, water-filled guage take a shit in less than a month. Same for me on both the gauge and pump. Quote Link to comment Share on other sites More sharing options...
SHIEF Posted April 21, 2004 Report Share Posted April 21, 2004 Hehe..you lost me at the carb part. Quote Link to comment Share on other sites More sharing options...
still2hi Posted April 21, 2004 Author Report Share Posted April 21, 2004 what happened to the gauge when it went bad? ie. did it not work at all or read wrong? Quote Link to comment Share on other sites More sharing options...
nurkvinny Posted April 21, 2004 Report Share Posted April 21, 2004 Originally posted by still2high: what happened to the gauge when it went bad? ie. did it not work at all or read wrong? The needle would barely register any pressure, even though the truck was running perfectly. I took the Jegs gauge off and bought a Barry Grant 0-15 lb gauge. That gauge is still working to this day (about 9 years). Quote Link to comment Share on other sites More sharing options...
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