M-135 Fuel Pressure?

[Dano McLaren]

Hi All. We are going to try to get my deuce started this weekend. The tank is contaminated so I am going to feed it fuel via a 12 volt fuel pump. The question is, what amount of pressure is required. Has anyone done this before.

[Stan Leschert]

When my mechanic gets back from Normandy, I will check.

We put a 24v frame mounted pump on, and a Holley pressure regulator. Make sure to add fuel water separator and spin on fuel filter.

You are going to have to modify the in tank fuel pickup, as it won't work with an external pump. It has an internal check valve that acts an over pressure bypass. There was a thread on Steel Soldiers which covered it. I added my findings.

I think that the PSI was in the 4-6 range, adjust as req.

[rob love]

Right from TM9-819A, Pressure is a low 3-¼ to 5 psi. There are a couple of bleed holes in the pickup line after the original in tank pump. One is right at the pump, which will not be an issue unless you let the fuel level get low. The other is right at the top of the pickup line, and this one will be a problem. You have to plug it with something or your pump will pick up the path of least resistance and pump mostly air.

I ran my truck with a 24V external pump for the first winter. Come spring I was able to run a gallon of acetone through the tank which cleaned it up to near perfection, and returned to the original in tank fuel pump, like the Gods intended. If you do run acetone, make sure you remove the fuel pump first, or it will turn the rubber mounts and the bottom plug into goo.

[Dano McLaren]

thanks Rob. I will let you know how it turns out.

[Dano McLaren]

After sitting for over 8 years, we got my M-220 running today. Drawing fuel direct from a Jerry can mounted on the step, then through an inline filter and to the carb. Purrs like a very large kitten.

[rob love]

Glad to hear it worked for you. Don't expect to go too far on that one measly can of gas though. They are a very thirsty truck.

[Dano McLaren]

Here are a couple of the shots Of the rigging Dave did for the fuel feed. Will be carrying extra can if we venture more than 50 feet from the shop.

[Phil Waterman]

Hi Danno

That adapter for a 5 gallon can is not a bad emergency fuel supply too add to a trucks emergency kit, that and some hose could solve a number of emergency fuel system problems.

Yes the point of fuel mileage for bigger trucks is well taken but even being able to drive 30 miles at a can filling is better than coming home on the hook.

Cheers Phi

[rob love]

You will actually run into a different problem than gas mileage when you feed a diesel vehicle from a fuel can. Only a portion of the fuel that is pumped actually gets burned....the remainder goes back to tank. It's purpose was for cooling and lubrication of the injector pump system. So as a result you will find that the jerry can will empty rather quickly, and eventually after a coupel of them, your fuel tank will be overfull.

I found this out during a typical bitterly cold Feb ex here in Shilo. One of the LSVW MRTs froze it's lines, and wouldn't run. It was impossible to thaw it, so we strapped a jerry can onto the front of the truck and fed the line to the fuel pump. The two guys running the truck had to continually siphon the extra fuel out of the main tank and put it back into the jerry can.

It wasn't perfect, but it got them through the ex.

In hindsight, I could have run a line from the return line at the tank back up to the jerry can. But the conditions were never there to use it again.

There are jerry can adapters made up for these and similar purposes. There were two types....gravity feed and siphon feed. When the new plastic cans came out, they also made similar adapters for use with the outside threads of the new can, although the earlier adapters could still be used sionce the cans had the early threads on the inside of the neck.

[DanJahn]

Gravity feed the carb from a gas can on the roof. No need for a fuel pump for just getting a engine running in this case.