Full Size Jeep Network

What about a buffer tank after the pump?

The tank would have a considerable internal volume and both the inlet and outlet would be at the bottom. When pressurized, the internal air would act as a spring, providing fuel pressure for short periods while the pump is sucking air.

The only problem I see is with longer fuel system priming times. But I bet a check valve would shorten that time...

You referring to a surge tank? I run a surge tank on mine -- it's installed under the hood where the charcoal canister used to sit. It's about a quart in capacity, and is fed by the low-pressure stock fuel system and mechanical pump. The high-pressure pump for my EFI is submerged in the can. Unless I completely empty the gas tank, any fuel in the surge tank will continue to feed the EFI -- even if the pickup tube in the tank is temporarily exposed due to fuel slosh.

Not exactly. Mine would use air pressure. But your approach sounds interesting.
Thanks.

Note that you must use fuel hose designed for full fuel submersion inside your tank. Otherwise it will fail in a short time! Regular fuel hose is not OK.

Yep, ordered up the exact same setup that Acct did for his. Same sock, and some submersible fuel line and stainless clamps. Plan to rent a flaring tool tomorrow, drop the tank and swap things out.

Anyone have decent instructions on how to calibrate your sending unit? I have an aftermarket poly tank for my 78 that has a separate sending and pickup. Fuel gauge reads 3/4 when I fill it up.

All you can really do is bend the wire that the float is on to get it to show the biggest range of fullness. Problem is, if you bend it to show F when full, you may run out of gas at 1/4 tank gauge reading.

I'm hoping this fix to get the sock to the bottom of the tank will help out with that. Nothing I can do to solve the fuel slosh problem though.

1979bettywhite wrote:I'm hoping this fix to get the sock to the bottom of the tank will help out with that. Nothing I can do to solve the fuel slosh problem though.

Pull your electric pump, replace your mechanical pump, and install a surge tank with an internal high-pressure pump. If you have a slosh/cavitation problem, it will be solved.

Though I suspect that getting your pickup down to the actual bottom of the tank is going to help things tremendously.

acct21 wrote:Though I suspect that getting your pickup down to the actual bottom of the tank is going to help things tremendously.

It did with mine.

Just wanted to say thanks to everyone on this thread for the help with the fuel pickup issue. I got the surge tank up and running and it’s amazing. I can run less than half a tank of fuel now! And a lot quieter than the inline pump was too.

Yeah -- surge tank is the bee's knees. Quiet, efficient, and pretty darn easy to install. Which brand did you end up with?

One advantage to the job I have is access to some odd junk. Today I was tasked with changing the fuel filter tank on a hmmwv. Somewhere in its past life someone had screwed up and cross threaded one of the bolts that holds the top on. They tried a helicoil but the military frowns on things not fixed to standard. So a new housing was ordered and I got the nod to swap it out. For some reason this thread popped into my head and I started looking at the old one which was destined for the scrap metal. Instead of tossing it out I gave it a run in the sand blaster to clean up decades of grunge. While the helicoil was tried, I think simply a bold and nut with washers would work just fine.
Work for what you ask?
Why, a surge tank of course.
I’ll have to look into how it needs to work exactly but I bet it will work. Keep just enough fuel in the tank to keep from any issues the extension for the sending unit doesn’t help with.
Take a peek, see what you guys think. Will it work?






As an added bonus it has its own filter inside.

Looks perfect!

Yep, that will work. Run your return line to feed it also, and the overflow back to the tank.

I use a similar setup from B.C. Broncos that uses a high diesel spin on filter with a modified external mount. Works great.