Fuel Pump Overheating & Vapor Locking

Hi guys,
since it started getting good & hot here in the desert South-West, the CJ has been doing badly. I can run it around town, but the times I tgried driving it to work, on the way home in the afternoon when it was nice and hot ( I drive into work at 5 AM when it's still cool) after about 25 miles it just quits. The fuel pump, which is mounted to the front of the skid plate is hot to the touch. If I let it cool down, all is well and it runs again for a while then heats up again and quits.

I have already insullated the feed & return lines from tank to fuel rail with Thermo-Tec wrap/sleeve from Jegs, but the problem persists.

Will moving the pump to the outside of the frame rails end this problem, or is there a bigger issue? And if I move it, where is a good out of the way spot?If I need to go with an in-tank pump, who makes a good one for the stock CJ tank?

Im really bummed that I havent been able to get this thing running well enough to play with, plus I need it to drive to work soon, as my dd Liberty will be down several days while I put a lift in it and rebuild the rest of the suspension (it just hit 200k).

 

I take it that you have an aftermarket electric fuel pump?
Is the original mechanical fuel pump on the engine gone?
Do you have fuel injection?

Electric fuel pumps work best pushing fuel and fuel under pressure is more resistant to vapor lock.
If you think the fuel pump is the culprit, I would replace it with a new one and mount it as close to the tank, and as far from the exhaust(heat source) as possible.

 

Yes, it's fuel injected. The pump is a high preformance BBK electric pump, currently mounted about a foor from the tank ( mounted to the front of the tank skid-plate).
It is pushing 45 psi right now, capable of much more,, so I know pressure isnt a problem.
I guess moving it to someplace outside the framerails will help.

 

Not neccessarily true.
If you have throttlebody injection(Howell FI), you are running WAY too much pressure.
15 PSI max.

Even if you have the MPFI(MOPAR) those run around 35-38 PSI.

Your fuel pump may be killing itself.

Maybe look into getting an intank unit from a 87-90 YJ 2.5L(TBI)

 

What kinda amps is the pump pulling???
The fuel should cool the pump.
Could the "sock" on the pick up tube be dirty, causing the pump to work harder?
Is there a "sock"?
Is there a restriction causing the pump to work hard.
Getting it out to "clean air should help if it's all good.
Joe
Just an old guys thoughts