Recent Topics
Anyone remember "in living color" ?
by car51
12 minutes 13 seconds ago
schedule / oil recom. for 2015 Honda Accord V6
by Viche
48 minutes 19 seconds ago
looking for a good garden hose reel
by bowlofturtle
Today at 02:03 PM
New WD Blue 2.5" hard drive beeps???
by Drew99GT
Today at 12:39 PM
Grease for Craftsman Snow Thrower
by GGorman04
Today at 11:19 AM
Napa syn $2.99 qt.
by pda1122
Today at 10:59 AM
Can you mix brands of DOT 4 brake fluid?
by enochian
Today at 10:50 AM
rust on stainless steel pool rail and ladder
by raaizin
Today at 10:50 AM
Anybody have experience with Lubrication Engineer
by gmh101357
Today at 10:43 AM
Oil for a ford 302
by mazdamonky
Today at 10:37 AM
93 mercury sable unlock steering wheel
by cptbarkey
Today at 10:24 AM
Ford F250-350 Interstate MPG with the 6.2L Gasser
by AirgunSavant
Today at 10:12 AM
Newest Members
stydel311, jackadf, rlb4, apenland01, 2ManyMiles
57767 Registered Users
Who's Online
97 registered (2oldtommy, 901Memphis, 2010Civic, 4ever4d, BarryinIN, 1foxracing, 11 invisible), 2006 Guests and 338 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
57767 Members
66 Forums
248370 Topics
4061349 Posts

Max Online: 2862 @ 07/07/14 03:10 PM
Donate to BITOG
Page 2 of 2 < 1 2
Topic Options
#3066278 - 07/15/13 04:54 PM Re: Duece and a half [Re: ridgerunner]
2cool Offline


Registered: 07/13/11
Posts: 604
Loc: Delaware
The engines in the olde Truck, 2 1/2 ton, 6X6, M-48, were compression-ignition engines designed by M.A.N. (Machinen fabrik von Augusburg und Nuernberg) built under license for the Army by Mack, Continental, White, and Hercules. The pump was a Bosch single piston distributor type, where the fuel lines from the pump to the injectors looked for all the world like reallly long spark plug cables. As the fuel entered the pump, it went through the Fuel Density Compensator. The density of the fuel would cause an adjustment of the quantity of the fuel injected, and change the injection timing. The theory was that the denser the fuel, the more energy. The denser the fuel, the more time it would take to burn.

IIRC, the Technical Manual called for 1 Qt. SAE 10 oil per 10 gallons of gasoline, just to lube the pump. It would get much lower mileage on gas, but it would go. I believe that even with a turbo, the output was 130 hp. But then the Army only planned on it going 35 mph in line-haul style operations.

Top
#3358955 - 05/01/14 02:42 PM Re: Duece and a half [Re: ridgerunner]
ironman_gq Offline


Registered: 04/30/14
Posts: 400
Loc: MN
The old ones would run on just about anything because the injection systems were a lot more robust and simple. The old injectors were just a poppet valve with a nozzle on one side, it fired once per compression cycle and didn't need to be too terribly precise in metering fuel. Same with the pumps, they ran at a couple thousand psi at most, The new fuel systems on these trucks are using electronically fired injectors that can fire 4-5 times per cycle and pumps that operate at 30 thousand psi. To do that everything must have very precise tolerances, a change in fuel viscosity or a little debris in the fuel and the whole thing falls apart and parts get damaged.

Top
Page 2 of 2 < 1 2