Multifuel Engine life - the facts from Uncle Sam

[SCSG-G4]

Orren,

The changes Bjorn mentioned were on the LDS-465-2 engines, not the LDT. There is a company that remanufactures the engines, but as a diesel for farm tractors, not as a multi-fuel. There are a number of posts here on the site, and a web search will turn up additional sources.

 

[Jesse6325]

I just ha to put my worth in,,
The way I look at it my deuce is 40 years old (1971 AMC general, I think) Same age as I am, And the truck runs better than I do.
The biggest thing you can do to keep them alive and going is proper maintenance and proper operation.
Hopefully if I keep those two things in mind she will last at least as long as I will,,,, And probably be cheaper to repair!

 

[islandguydon]

My 2 centavos is this:

The oil is the life blood of any engine, keep the oil full and clean and operate the equipment the way it is supposed to be operated and there should be minimal maintenance expenditures.

 

[bearboley]

I did a little searching, and the engine in the White 2-155 farm tractor may share the multifuel block, but it is not the same engine. It is diesel only, has a 17:1 compression ratio, has a PTO power of 157HP, and has a governor that won't allow it above 2200rpm.

RPM is the key here. The military is perfectly willing to compromise longevity in an engine for the potential of increased performance - when you really need it.

A farmer is never going to need to push his engine to the red line, but rather is going to keep it at the governor, where the engine leads a comfortable cushy life. The farmer knows that he can barely make a living off of his fields if he keeps his tractor investment going for 20 or 30 years. Many tractors get passed down from generation to generation. He knows that if it breaks, he will have to pay for the repairs, and will have to suffer the down time.

A military truck driver is often in a field of fire, wants to get the **** off of the road quickly, and is frequently a kid. A kid that has no stake in the costs of maintenance and repair. It is not his truck, after all.

-Chuck

Put a couple 18yr olds out in the field and see what happens. We used to beat on dads tractors like rented mules. We used to tie a string on the govenor arm and race on the road. I think the duece is not much more than a glorified wagon designed to run at 35mph. High road speed and high rpms will kill it.

 

[m816]

I read all 9 pages and DD definately knows his stuff. But I would respectfully submit that the manual for the multifuel engine states very clearly that the engine is " medium duty" engine.That being said, What these trucks, particularly the five tons were performing way more than what could be expected from a "Medium Duty" engine. We loaded those trucks and used them hard. Not because we didn't care,but because there was a critical job to be done and lives depended upon getting the loads delivered. I drove wreckers back then and except for a very small minority of knuckleheads, the drivers were very proud of their trucks and aside from tire chaging details , they broke their butts to keep them in shape. I hauled many wrecks and damaged vehicles from road hazards and broken frames and driveline breakdowns rather than any blown engines. I drive these trucks hard because they can mostly handle any abuse. Give them good maintaince. I try not to hurt them but some times an old engine will die just like the troopers who drive them. I have a egt gauge and a boost gauge on mine now and don't over rev the engine and don't hold the rpms high for long periods any more. I still love the sound that they make. Just like the Harley's. You know we are coming

 

[islandguydon]

M816,

In your opinion whats the RPM hi point that is safe for the engine for road trips..? When i log miles I try and stay between 21-2200RPM no higher. Every once in a while I will look down and see 2500 then I back off back down to 22. Thats how I drive anyway.

 

[RodUSMC1962]

We drove all our vehicles much harder than they were designed to be driven. I never drive my military vehicle like I did uncles.

 

[lawdog1623]

no problems with mine at all. Mine is not exactly a daily driver, but im very anal about every little detail of maintenance on my truck. If its low on coolant i wont drive it. If it starts running warm, its parked until i figure out the issue. Low oil? I find out why before i drive it anywhere. YES I DID SAY ANAL!

 

[ModernDieselLegion]

the key to these motors is like you have all mentioned, fluids. they were over-sized and over engineered for their application. Take it from me (diesel shop owner), letting the motor warm and cool is extremely important because every internal parts rides slightly different when that motor is completely awash with heat versus when it is cold. Quick shut offs and fast starts leading immediately into aggressive driving is bad for rings, bearings, and the head gasket.

im sure these trucks were pushed in war time but i guarantee we have pushed our XM820 harder than many or most were pushed during war and it has not had a single hiccup. doesn't even drip oil.......which reminds me....again as a diesel shop owner and mechanic...im sick of hearing "if it doesnt drip something's wrong with it"


lastly a big killer of these trucks is the build quality. my personal civvy truck runs a 6.7L cummins. i blew the head gasket towing and had the deck and block checked. total variance on the plane of the head was from -.004 to +.012 That is on an american-made Cummins motor. Imagine what the quality of the build was during war time???? They slapped these trucks together and hoped the overly big, under fueled motors would hold up. Many didnt.

 

[ProudAmerican]

Curious - have a 1969 Multi Fuel Hercules engine - anyone ever or used additive for less friction - run cooler - in the engine ? I have had some success with Moto Kote on my 2004 Ford F-150 truck - 188,000 miles - 99% expressway driving ! Ralph

 

[73m819]

the key to these motors is like you have all mentioned, fluids. they were over-sized and over engineered for their application. Take it from me (diesel shop owner), letting the motor warm and cool is extremely important because every internal parts rides slightly different when that motor is completely awash with heat versus when it is cold. Quick shut offs and fast starts leading immediately into aggressive driving is bad for rings, bearings, and the head gasket.

im sure these trucks were pushed in war time but i guarantee we have pushed our XM820 harder than many or most were pushed during war and it has not had a single hiccup. doesn't even drip oil.......which reminds me....again as a diesel shop owner and mechanic...im sick of hearing "if it doesnt drip something's wrong with it"


lastly a big killer of these trucks is the build quality. my personal civvy truck runs a 6.7L cummins. i blew the head gasket towing and had the deck and block checked. total variance on the plane of the head was from -.004 to +.012 That is on an american-made Cummins motor. Imagine what the quality of the build was during war time???? They slapped these trucks together and hoped the overly big, under fueled motors would hold up. Many didnt.

Think your WRONG, these older engines wear built under a different mind set, then it was "I WILL DO MY JOB AS BEST AS I CAN" hence a quilty product, now days the thought by a lot is, "I'M HERE, THAT IS GOOD ENOUGH" hence you end up with the above issue and CRAP products

 

[stumps]

Curious - have a 1969 Multi Fuel Hercules engine - anyone ever or used additive for less friction - run cooler - in the engine ? I have had some success with Moto Kote on my 2004 Ford F-150 truck - 188,000 miles - 99% expressway driving ! Ralph

I use this stuff called Shell Rotella 15W40. It reduces friction, provides cooling, improves cold weather starting, has special high pressure additives to protect the bearing surfaces from galling, and protects against acids and moisture. I add it by the pale full at each oil change, about 5.5 gallons.. I know it's expensive, but it seems to keep my MF engine humming along nicely.

-Chuck

 

[ProudAmerican]

OMG ! 7 gallons of Shell Rotella - go's into the metal parts - so still adding the requirement oil to the engine ? Ralph

 

[scopionf89]

I saw a Duece with 145,000 milies on it on ebay once said it was used by a guy that was getting out of the military surplus store business. I don't know how many engions he had gon threw I imagin not many because if he had he would have bought a civilyan truck. I can say this I have put just over 5,000 miles on my Duece and have not had any engin problems it has 11,000 mililes on the odomiter it was depo overhald in 92. Know the m1078 that replaced the m35a2 thats a pice of junk. I hade one back in Ft. Hood that had only 6,000 miles on it before the transmishio went. Wile I was in korea I had one that had 5,000 miles on it and its engion went. It blue its head gasket and did some thing to the head its self requiring the hole engion to be scraped. I am all in favor of going back to the M35a2 and getting rid of these computerized pices of junk that we have now.

 

[whatadeuce]

Hello desertfox, and what's a PRELUBER ?

 

[whatadeuce]

hello everyone, and the deuce I just bought has no turbo, and has 22,000 miles on it. The previous deuce I had was used to deliver tires and rims from my 19 and 42 FORD airport snow blower 1 1/2 ton with MARMON HERRINGTON suspention. The deisel service dealer wouldnt unmount the rims from the 42 ford, said the rings would pop and cut off his head! But at that time I asked him to check my deuce engine, and laughed when he advised to wait till it reached 500,000 miles ! Now thats confidence I appreciate. WHATADEUCE

 

[whatadeuce]

Im with you SCORPIONF, I believe the art of driving includes manual transmissions, and electro-mechanical controls ONLY. All repairs shoiuld be possible in the field, not necessarily in the home shop. WHATADEUCE

 

[whatadeuce]

And where can I purchase a preluber? Also, Will the use of a preluber after engine shut down , provide full oil pressure to the turbo bearings?

 

[emr]

They are far from crap products, very very far, That one written opinion is derived from his experience, and not as i see it years of testing by a group including manufacturers and the Army, period. Things like this happen many times in civilian life and military life, Sometimes right , sometimes wrong.I think the majority of us know just how rugged and tough these engines and trucks are, they sure have proved that paragraph wrong, do to the test of time, how many are still in service around the world, period, Funny how many guys are going to be scared of these engines now, after they have been serving longer than any other in history, Funny I think, I am not arguing like said not to in first post, I am stating facts... Oh and I must add, U will find articles like that about the 939 trans, all proved false also, driver error, like the more experienced guys are saying, was the largest part of problem , notice they NEVER were taken out of service, notice there are NO bulletins other than that to drive a multi is different, ..That is the basis of it all, they worked well after the 427 for a long long time, Most guys still dont understand these are tactical trucks, maintenance and ability to drive a multi is the biggest key, Like anything new, they usually have to be taught a few times how to drive em, sadly allot of guys who buy em now, want to race em down the road, then when something goes wrong they will blame the truck, but U know what, 99% of what goes wrong is Human error Oh my first deuce, had almost 10,000 on it when i got it, It had 40 something on it when i sold it, ran her like a truck, and she is still strong today, and will be for many many years to come. Just broken in I say The quality of oils today is superior also, Just think straight 30 wgt was good enough for many many years. never a bulletin on that either, because it worked. With all that said, it is a medium duty engine also

 

[whatadeuce]

hello Randy...