Motor Question

[Cigarjoe]

I am looking at some dueces to buy, and when I am looking under the hood I am seeing a data plate on the right side of the motor that says Hercules multifuel but the fuel tank says diesel fuel only. I'm confuses as to if it is multifuel or not? The other question is what does multifuel mean? Can I dump anything that burns in it and go?

 

[Boatcarpenter]

I'm not trying to be a wise ass here, but if you search you will find hundreds of posts that will answer all your questions. You also will earn a lot about the vehicle you are thinking of buying.
BC

 

[Marlboro]

Some trucks had the fdc bypassed, but from threads i've read on here you can still burn other fuels in the truck. You can dump most anything combustible into the tank the high compression allows you to do so. I've never ran anything but desiel and some motor/trans fluid from time to time.

 

[poppop]

Most multi-fuels had the fuel density compensater bypassed, When that was done diesel only was stenciled on the tank. It will still burn a varitiy of fuels including WMO and ATF. As stated above there are lots of posts on the subject.

 

[wsucougarx]

Not exactly on the stencilling of diesel only on the fuel tank. Both my USAF contract trucks have "Diesel Fuel Only" on the tanks, however, the FDC is NOT bypassed. Whether or not the FDC is bypassed is beside the point. You can still run anything with a BTU rating through your tank. The FDC just helps to maximize power based upon the density of the "fuel" you're using.

 

[Keith_J]

While you may get away with burning waste motor oil, used deep fryer oil etc, it isn't a good thing for the high pressure side of the system. Multifuel was designed to burn anything from #2 heating oil to mogas, including most jet fuels, kerosene as an alternate. But all motor vehicle fuels without any significant particulate matter, unlike used motor oil.

What will go wrong if non-fuel alternates are used? Eventual wear of the nozzles on the injectors with used motor oil. And gummed-up needles on the injectors with waste cooking oils.

The need for this was when the battlefield had gasoline. Since the 1990s, the battlefield is one fuel, JP8. But in many cases #2 diesel is much cheaper, hence the substitution for ground equipment and the wording on the tank.

 

[Jake0147]

Agreed. If the FDC is bypassed, the horsepower output will change with alternate fuels, rendering the vehicle out of specification, therefore not mission ready. Alternately, some were stenciled such to reflect local or regional administrative policies. The multi fuel ability is designed into the pump (with the pump part being "fine tuned" for final horsepower output by the attached fuel density compensator), injectors, and combustion chambers. Unless you have done major engine work, you still have the original multi-fuel ability regardless of painted markings.

 

[Cigarjoe]

Thank you all for your replies. So what I getting is that I can run what ever, but it will run better hooking the FDC back up. Did they tend to leave them on the truck and just bypass them, or did they remove them? Is it fairly easy to hook back up? I am looking at a M35A2 with CARC paint, all fiberglass troop seats and rails, new troop top, new cab top, multifuel motor with 24000 miles, winch, heater, steps for rear, and little to no rust, for $5500. Is this something I should jump on?

 

[gimpyrobb]

No, the fdc is ONLY used to keep power output of the motor the same between different fuels. If it is bypassed, do not hook it back up. It will rob you of power and have the chance to send fuel to the crankcase and dilute your oil! The trucks run best on diesel, but will still run on other stuff too.