glow plugs on deuce?

[Keith_J]

The "multi" in multi-fuel meant use of Mogas in addition to diesel or jet fuels. Most true diesels just will not run on gasoline. And the 6.2 GM was never designed with that capacity as the injection pump is lubed with the fuel, gasoline would cause rapid wear.

When the Hypercycle was being fielded, there were many vehicles in the military fleet which were gasoline fueled. And most of the larger trucks (10 ton and up) as well as armor/artillery were diesel.

The 1980s introduced the "one fuel" battlefield. This is when the GM CUCV was selected to replace the Dodge CUCV (powered by a gasoline 318 CI V. Gasoline gensets were being replaced by much heavier diesel sets. And finally by the 1990s, the M2 burner used in field kitchens was replaced by a diesel/JP-8 burning Modern Burner Unit.

Nearly every multifuel truck has a yellow placard listing acceptable fuels. Since the injection pump on these engines is lubricated by engine oil, gasoline does not cause undue wear

 

[sandcobra164]

ODdave,
The 6.2/6.5's injector pump's are hardened to combat wear due to use of JP8. As I'm sure you know, JP8 is a very "dry" fuel that provides very little lubricity to the fuel system components. I've been to manufacture training on alot of the new equipment the USMC has and they mostly adopt COTS (Commercial Off The Shelf) technology and have "dosing" filters incorporated into the fuel system. The "dosing" filter adds the lubricity and eliminates the need for changing injector pump components. The "dosing" filter's seem to all share around a 250 hour change interval as well. It seems the military has 1 of 2 choices on injector pumps, harden the components or use a dosing filter. The latter was certainly new to me but I think it works better for the manufacture. IMO, it gives the manufacture an opportunity to void a warranty claim if the military cannot prove that the dosing filter was changed out on time and at the same time sell a costly injector pump.

 

[ODdave]

so, correct me if i am wrong, but the hardend H&R so they can run JP8 correct?

 

[mudguppy]

...i dont think uncle sam would have shelled out the extra coin to have all mil-spec stanadine DB2 pumps outfited with a hardend head and rotor if he wasn't expecting these trucks to be ran on something other than the standard No2 diesel with all of the correct lubricity additives. ....

this is true, except it was never expected to be run on No.2 - the 6.2/6.5 was always intended to be run on JP8.

...would you rather had a 6.9? and a ttb front axle? ...

absolutely - the 6.9 is renowned for it's reliability and is exponentially more reliable than the 6.2/6.5 family. and the only thing the TTB fronts would have been found on is the CUCV family; and since the TTB affords better on-road manners than a straight axle and similar articulation offroad, i wouldn't be skeered to drive one around post. they eat tires faster, but in the Army, i could get new tires any time i wanted, so...

however, this is moot, because the one-ton Fords in that era all had solid axle, hi-pinion, kingpin Dana 60s.

... Uncle Sam picked the best suited of the 3...

you'd think, but that's not how Uncle Sam works. of all qualified bidders, Uncle Sam must go with the lowest bidder, not best product.

so, correct me if i am wrong, but the hardend H&R so they can run JP8 correct?

yes. JP8 is extremely similar to No.2 diesel, but without a lot of the lubrication additives. JP8 is a turbine fuel; therefore, the military can carry one fuel to run HMMWVs, trucks, tracks, M1s, and Helo's.

 

[ODdave]

done with this thread.

Wow some ppl just like to argue, I'm done. BTW, Thankyou for owning a 6.0 I make good money fixing them. Goodbye thread.

 

[saddamsnightmare]

February 5th, 2010.

Gents:

With all the controversy over Multifuel this and IDI that..... The gent's original question is whay wasn't the deuce fitted with glow plugs. At the time of the program coversion (approximately 1965), it was fairly uncommon to use glow plugs in any large displacement diesel as a starting aide, least of all in the military where complexity was to be avoided. The USATC General Electric 44 ton locomotives used two Cat V-12(?) bulldozer engines as power, and the accepted cold weather starting system there was two kerosine burning hot water (block) heaters to get the engines up and running. The deuce could not affort the luxury of a 1/2 hour startup routine, so, from what I can see, mostw were fitted with intake flame heaters.
From what I have seen in my own truck, if the starter and batteries are good, the flame heater is little needed above 20*F+ (starter solenoid problems excepted) as the truck kicks right over. One does not have to wait for the glow plugs to heat and the truck can move almost immediately. American diesels have been pretty much poorly designed from day one to handle cold weather starts, whereas most European, and more particularly, the Deutz units, tend to handle cold starts much better. I had a generator set with a Deutz FL-912 4 cylinder air cooled diesel, and it could start without glow plugs (it had none), no ether (it had a measured shot system), no preheating of the oil, in -20*F on two cranks. The first time it would catch and run rough for 30 seconds, then usually stall, the second time it would run rough for 30 seconds, then come up to speed and load. The machine was designed to run in temperature conditions from the equator to the Arctic, and I never saw any evidence it would not do it. I have yet to see an American diesel do the same in below zero cold soaked conditions.....
The deuce does pretty well for the time and place it was designed for and the services it was used in, I have seen few more modern trucks that can do what it does, consistently, under the roughest service conditions...

Just my two cents worth,

Cheers,

Kyle F. McGrogan

 

[greenjeepster]

Is the Multifuel a prechambered diesel or toroidal diesel? Glow plugs generally are only used in pre-chambered diesels. Toroidal diesels do not need glow plugs.

Many large diesel trucks do not have glow plugs.

Edit: I read back through the posts and Mudpuppy hit the nail on the head. The 6.2 is a pre-chamber diesel.. the Deuce is a toroidal (direct injection) diesel. The glow plugs go into the pre-chamber... no pre-chamber, no glowplugs.

 

[Keith_J]

Hypercycle is direct injection with a spherical chamber. Intake rotation is vertical where in the modern direct injected diesel has the toroidal combustion chamber. The difference? Hypercycle is designed to sweep pooling liquid fuel into the fire more effectively.

 

[mudguppy]

Wow some ppl just like to argue, I'm done. BTW, Thankyou for owning a 6.0 I make good money fixing them. Goodbye thread.

i guess that was a shot at me? that's ok - my 6.0 doesn't need work and likely won't.

sorry you feel the need to get defensive and offended; there's no need. i thought we answered your questions fairly well.


but, i still believe that the high compression design of the MF eliminates the need for GPs. that doesn't mean it's right, just a theory.

 

[ken326@yahoo.com]

Well thanks for those answers now here's another question same topic. I have a a3 model which is newer with a cat engine still no glow plugs
thanks for your opinions

 

[mudguppy]

that's ok, my Cummins doesn't have plugs, either.

 

[greenjeepster]

Diesels without glow plugs are far more common than those with.

I have never driven an over the road truck that had glow plugs... Can't think of any that have them. Seems that glow plugs are reserved for small diesel vehicles... Probably because they are an added cost and if you are driving diesel for a living you will know how to start one without them...

 

[derby]

I am no expert, but from what I know of it (and has been mentioned) the multi is a direct injection wich uses a hyper cycle to aid in combustion. My mercedes has pre combustion chambers with glow plugs. The pistons in the Multi have a "bowl" that fuel is directed to and causes the swirling. The Mercedes has flat (mostly) piston and combustion is started in the pre combustion chamber wich is in the head. I don't think it has to do with compression ratio as the Mercedes is 21.5/1 more of a combustion chamber design. They still use glow plugs on newer diesels. They can be a maintenance problem, and without them they will not start. This may be one reason they were not designed into the multi. I know my Deuce will start better at lower temps than the Mercedes. more so now that I have a water pump heater installed in the Deuce.

 

[Heavysteven]

I disagree, glow plugs are common place. Bobcats, excavators, powerstokres, cummins, cat, all have glow plugs

the multi using alternatives to glow plugs, flame heater and ether

 

[greenjeepster]

"All have glowplugs" Wanna bet a weeks pay on that I can list many cats and cummins diesels without glowplugs.

Many small industrial diesels do have glowplugs... The big on highway diesels more often do not.

 

[nk14zp]

 

[mudguppy]

Cummins don't have glowplugs; they use heating elements in the intake manifold (grid heaters).

but you can add duramax to the list.

 

[tm america]

what makes a multi am multi has more to do with the hypercycle and the way the fuel enters the cyclinder than it does with the compression ratio.Most deisels mist fuel into the cyclinder while the multi it is sprayed right into the cup in the top of the piston . they probably need the high compression ratio just to be able to ignite the fuel from a liquid form vs a vapor .Yes you can run different fuels in many deisels and get away with it for awhile but that doesnt make them a multifuel..i want to see how good your 6.2 starts at 0degrees out running on waist oil or try running gas in it that should work out real good for you

 

[mudguppy]

guys, p-strokes, d-maxes, and cummins all have fuel bowls in the piston....

 

[greenjeepster]

Why do diesels not have spark plugs