Fueling & Injection - 120*F Fuel pump overheating - help?

Ok, well, the problem is simple. The fuel pump seems to be working against itself once fuel pressure builds to about 60-65 psi. This is causing it to overheat pretty badly. Once it starts to overheat the pump begins to make this sucking-whining sound like a crimped hose and fuel pressure begins to fluxuate then drop off. Once that happens, I might as well shut the engine off cause its gonna go into a starvation situation within a minute. How do I keep the pump from overheating. I don't honestly remember which fuel pump it is.

Thanks! :bang:

I assume that the pump is not mounted in the tank. What type of fuel pressure regulator are you running? With the 98+ ls1 the fuel rail is returnless. You would have to build the system with a regulator after the pump and a return line from the regulator back to the tank. if this is set up correctly and the pump still overheats, it may be the pump isn't designed for the pressures your asking it to produce. Also if the pump isnt being fed with enough fuel it will not pump. (like you said 'pinched hose'). ideally you would have a feeder pump in the tank, or a sump/feed in the bottom of the tank with the inline pump mounted lower than the sump pickup. more info would be helpful to brainstorm ideas.

I assume that the pump is not mounted in the tank. What type of fuel pressure regulator are you running? With the 98+ ls1 the fuel rail is returnless.
Well, you probably know more about the fuel system than I, but I have a line that is wrapped in that heat wrapping besides the incoming fuel line up by the fuel rail, and it looks just like a return line setup that i have on my 5.0 Ford EFI. It even has the weird quick-disconnect that fuel lines have, and the steel part of the line is the same color (whether or not that has anything to do with it) as the incoming fuel line.

That said, if it is a return line, i'm running a stock regulator, if it isn't then I'm not running any. This engine came out of a CHP Camaro just as background info.


You would have to build the system with a regulator after the pump and a return line from the regulator back to the tank. if this is set up correctly and the pump still overheats, it may be the pump isn't designed for the pressures your asking it to produce. Also if the pump isnt being fed with enough fuel it will not pump. (like you said 'pinched hose'). ideally you would have a feeder pump in the tank, or a sump/feed in the bottom of the tank with the inline pump mounted lower than the sump pickup. more info would be helpful to brainstorm ideas.
A little more background about the setup - its going to be going into a 1974 porsche 911, and the feed will pickup from the bottom of the tank, but probably run out of the top/side. The tank will have to be custom made eventually, but thats a few weeks away still. Right now, the pump is in-line. It is getting plenty of fuel - the 2 1/2 gallon tank we have hooked up is basically a big sump, the fuel feed is the bottom of the tank. If this were in the car I wouldn't do it this way, but for an engine stand, it works.

All this said - if I don't have a regulator/returnline system already, all I have to do is install an regulator inline anywhere past the fuel pump, but before the rail? If thats the case, what is a good inline regulator to use? Or maybe you have another idea? I will try to post a picture sometime in the morning of the system - be warned, its BASIC.

ok, heres an image of what I believe is my return line fuel system, and anyone who knows what it really is, PLEASE tell me


http://www.storshun.com/porsche/lines.jpg

That's not a return line.. It's the charcoal canister purge line (EVAP system). That line carries fuel vapors from the charcoal can in the back, to the intake manifold to be burned by the motor. Emissions stuff. The "What's this?" marked unit is the EVAP purge solenoid.

The LS1 Camaro never came equipped with a return line (at the motor). The fuel return is done back by/in the fuel tank...

The LS1 Camaro never came equipped with a return line (at the motor). The fuel return is done back by/in the fuel tank...


Ahh - it all makes sense!!!