Torque rating

[GeneralDisorder]

I believe you re the emissions thing, but my engine has a plate on top that specifically says it's EPA emissions compliant...do you think this means it's not the original engine?

Also, if the A2 has a better transmission controller, but the same trans is it an easy upgrade?

The engine has not been swapped. CAT just sold Stewart and Stevenson an off-the-shelf truck engine. It met certain EPA emissions and had stickers to such effect because at the time it met the military requirements AND the EPA requirements without having anything the military objected to. 30 years later that's no longer the case as the military doesn't want a bunch of equipment that has emissions-only related components that require special servicing, parts, or fluids. The 3116 met the EPA diesel emissions in the 90's without any of that so it got the rating and all of them got the sticker. As additional equipment started to be added for purely emissions compliance the military wasn't interested and as they FAR outweigh the EPA in such matters they continue to use engines that meet their needs and also meet various older EPA requirements but absolutely don't meet any current ones.

I am not aware of anyone having swapped an A0 WTEC II to a WTEC III. It's a lot different. Probably possible but I haven't seen it. The later and current trucks got an improved transmission around ~2005 and the WTEC IV controller. WTEC III and IV both have a control panel that is completely separate from the TCM and they are located on opposite sides of the truck, while the WTEC II has the TCM and control panel integrated into a single unit under the dash gauge panel.

 

[BigMontana]

Yeah the new diesel emissions stuff is a pain in the ass. It fails all the time for no real reason, they also make the engines run so hot they take a huge hit to longevity.

I am kind of curious if a little splash of propane on top of the diesel would clean up the emissions more than most folx think ... I might experiment with that at some point, see if I can get a good sensor on the tailpipe...most folx doing propane are going for big gains, I'd like to see a little synergy, shoot real light at cruise.

The engine has not been swapped. CAT just sold Stewart and Stevenson an off-the-shelf truck engine. It met certain EPA emissions and had stickers to such effect because at the time it met the military requirements AND the EPA requirements without having anything the military objected to. 30 years later that's no longer the case as the military doesn't want a bunch of equipment that has emissions-only related components that require special servicing, parts, or fluids. The 3116 met the EPA diesel emissions in the 90's without any of that so it got the rating and all of them got the sticker. As additional equipment started to be added for purely emissions compliance the military wasn't interested and as they FAR outweigh the EPA in such matters they continue to use engines that meet their needs and also meet various older EPA requirements but absolutely don't meet any current ones.

I am not aware of anyone having swapped an A0 WTEC II to a WTEC III. It's a lot different. Probably possible but I haven't seen it. The later and current trucks got an improved transmission around ~2005 and the WTEC IV controller. WTEC III and IV both have a control panel that is completely separate from the TCM and they are located on opposite sides of the truck, while the WTEC II has the TCM and control panel integrated into a single unit under the dash gauge panel.

 

[Ronmar]

I would be surprised to see any engine or engine compartment made after 1980 that didn't have some kind of EPA sticker, not that it was difficult to get that sticker for a diesel then, as the requirements were not difficult, and basically the engine achieved the standards naturally/thru normal operation. Those were the good days, where the required standards were achievable by simply improving efficiency, and the diesel already being pretty efficient, had little difficulty. The Cat MUI injectors run ~30K PSI, so those engines have always had good atomization and fairly clean burn, plus that nice cat clatter

It may have been that ease of compliance then, that encouraged marketing more diesels to the personal market, which of course pushed more diesel pickup engine sales and highway use, Which sadly led to tighter regs and diesel engine requirements like those used on gas engines in the 80s-90s(EGR and catalytic converters) being applied to diesels(DEF instead of cats) plus more complicated engine tuning making these systems operate.

My sticker says compliant with highway regs for 93. But if you read closer, the fine print also says that it also falls under a title 40 CFR military exemption. If you enter the serial number over on Catparts.com you can get the build date and specs for it, as well as look up the parts they specced for the military s/n range of production(225 and 290 hp turbos and governors)… but basically when they setup these engines, they were not really concerned with the EPA…

propane having high water content and absorption qualities as it expands can enhance higher power operation, like water/alcohol injection, it acts like a chemical intercooler and will enhance volume and simultaneously add fuel to help match that volume. But because of its lower BTU content I do not think it will add all that much to lower end operations. I have used it on my slow speed generators as an alternative, to extend my diesel and oil fuel supplies. Its moisture content also help keep the engine cleaner. Basically at lower loads as you roll on the propane, the governor will roll off the diesel to maintain its commanded RPM, until you hit the point where the engine will start to mis-fire as there is not enough diesel left to ignite under compression. The only places I have ever seen it used on road, it was used like nitrous, in conjunction with full rack/full boost application. for this application a boost pressure sw would probably be a good way to control its application…

 

[BigMontana]

See, that all ties back to your original misunderstanding, the reason they passed the portion of the EPA they DID pass (yes they were exempt from lots of it). was because of the EPA setting a fuel air mix that favors a lean condition...if you crank that top kick screw a little it runs cooler and a little dirtier.

a bit back you said something about temp control. are you having, or did you used to have temp control issues? how'd you fix them?

-Deke

I would be surprised to see any engine or engine compartment made after 1980 that didn't have some kind of EPA sticker, not that it was difficult to get that sticker for a diesel then, as the requirements were not difficult, and basically the engine achieved the standards naturally/thru normal operation. Those were the good days, where the required standards were achievable by simply improving efficiency, and the diesel already being pretty efficient, had little difficulty. The Cat MUI injectors run ~30K PSI, so those engines have always had good atomization and fairly clean burn, plus that nice cat clatter

It may have been that ease of compliance then, that encouraged marketing more diesels to the personal market, which of course pushed more diesel pickup engine sales and highway use, Which sadly led to tighter regs and diesel engine requirements like those used on gas engines in the 80s-90s(EGR and catalytic converters) being applied to diesels(DEF instead of cats) plus more complicated engine tuning making these systems operate.

My sticker says compliant with highway regs for 93. But if you read closer, the fine print also says that it also falls under a title 40 CFR military exemption. If you enter the serial number over on Catparts.com you can get the build date and specs for it, as well as look up the parts they specced for the military s/n range of production(225 and 290 hp turbos and governors)… but basically when they setup these engines, they were not really concerned with the EPA…

propane having high water content and absorption qualities as it expands can enhance higher power operation, like water/alcohol injection, it acts like a chemical intercooler and will enhance volume and simultaneously add fuel to help match that volume. But because of its lower BTU content I do not think it will add all that much to lower end operations. I have used it on my slow speed generators as an alternative, to extend my diesel and oil fuel supplies. Its moisture content also help keep the engine cleaner. Basically at lower loads as you roll on the propane, the governor will roll off the diesel to maintain its commanded RPM, until you hit the point where the engine will start to mis-fire as there is not enough diesel left to ignite under compression. The only places I have ever seen it used on road, it was used like nitrous, in conjunction with full rack/full boost application. for this application a boost pressure sw would probably be a good way to control its application…

 

[GeneralDisorder]

See, that all ties back to your original misunderstanding, the reason they passed the portion of the EPA they DID pass (yes they were exempt from lots of it). was because of the EPA setting a fuel air mix that favors a lean condition...if you crank that top kick screw a little it runs cooler and a little dirtier.

The military was definitely not interested in rolling coal. They went through that with previous generations and visible diesel exhaust gives away your position.

But really the entire point of the FMTV concept in the late 80's and early 90's was to replace the M35, 800 series, and 900 series of trucks with a single platform that would use (and this is VERY important)..... "commercially available OFF THE SHELF parts" - this was a MAJOR consideration to the design. They wanted cheap parts by leveraging the commercial truck industry for engines, transmissions, axles, lighting (that's why they have 12v lighting not 24v like a HMMWV), brake systems, etc, etc. The entire cab was even licensed from the Steyr 12M18 - switches and gauges, and all manner of parts are basically off the shelf truck parts that are painted black and green.

The CAT engine was just one more off the shelf part that fit the bill - EPA compliance was just a side effect of using cheaper off the shelf parts.

Times have changed since the US Army offered the FMTV contract/concept and the pendulum has swung away from that concept - in the mid 2000's they realized everything had to be armored - even the support units due to lessons learned in the middle east theatre and the media backlash about body armor. That drives costs up and drives the Army away from commercial parts. They still use as many as they can.

 

[coachgeo]

....

But really the entire point of the FMTV concept in the late 80's and early 90's was to replace the M35, 800 series, and 900 series of trucks with a single platform that would use (and this is VERY important)..... "commercially available OFF THE SHELF parts" - this was a MAJOR consideration to the design. ...

yup-ish... twas the plan..... but if recall what read...... it was a plan MANDATED by Obama administration? Not a bad concept in keeping supply chain easy to to get parts and to keep cost down...... just trade off ... being mandated; made it harder to go back to custom parts (like armor) cause it was not anywhere in the commercial realm.

 

[Ronmar]

I don’t think I misunderstood anything Not quite sure why you drug EPA into it, but the simple fact remains mechanical fuel injection is not self correcting, and without the proper tools to gauge changes, you can drive it out of balance and ultimately over fuel and cause damage, same as any other engine… I think perhaps you are misunderstanding me… Don’t worry, I get that a lot, in that these engines had some horribly restrictive tune to meet some emissions standard, when in the 90’s I don't think any really had to be tuned like that to get that sticker… Still waiting for all the people who have done the nip and tuck tune to chime in with all those glowing performance reports, dyno charts and success stories…

As for temp control, on the A0 they deviated from cats normal cooling system design for the 3116.. in cats design, the warm coolant comes out of the head into the thermostat housing. They use a bypass thermostat, so until the coolant reaches thermostat opening temp, it gets sent straight down thru a short length of hose to the water pump to pass back thru the engine until it is warm. Sounds pretty standard right?

On the A0 LMTV they use a special made thermostat housing and water pump. The 1” hose port out the bottom of the thermosrat housing was recast with a 90 degree elbow pointing forward. The top 1” hose port on the water pump was cut off and a freeze plug installed. That thermostat housing output passes across the front of the engine thru a stainless pipe and down to the transmission heat exchanger on the drivers side. That transmission has a lot of mass and surface area(makes a great radiator).

All the engine heat gets sent there and when it is below 70, the engine will not get to thermostat temp without the trans being given enough work to actually start producing heat… @68F Even placing the engine in drive and elevating the throttle slightly(cold wx warmup procedure), it still takes nearly 15 minutes for the transmission to shift from a heat sync to a heat source, and another 10 minutes to get the engine to op temp, and thats with a 178F thermostat… The only reason I can see them doing this is perhaps they thought in very cold climates they could warm the trans, or if you were really working the trans it might overheat if the engine didnt get warm enough to open the thermostat enough to circ coolant thru the heatex. Isnt that what radiator covers are for…

This was probably the brainchild of the same guy who thought matching 4ea 120AH batteries in series/parallel with basically a pair of 50A alts was a good idea… Aaah the things that go on in the land of milspec…

They did away with this Wonderfull bypass plumbing scheme for the A1, probably because the HEUI engines need proper stable coolant temps.

Watch my cooling system video #1, I returned the cooling system to the original cat plan and instead sent the cabin heater return to the transmission heat exchanger port. My water pump was leaking anyway so instead of trying to source the specific, harder to find military modded pump, or modding a civilian one myself, I was able to fit a commonly available 3116 pump… The thermostat housing was easy to mod as they left plenty of straight section left to fit a hose to after cutting off the elbow from the bypass outlet. I also removed the coolant recirc lines from the pump and housing as I was relocating the expansion tank. This simplified the plumbing around the engine quite a bit. I also installed a 190F thermostat. Now it idles right up to op temp fairly quickly and if I feel the need to send heat or flow to the transmission heatex, I simply open the heater valve in the cab…

 

[GeneralDisorder]

yup-ish... twas the plan..... but if recall what read...... it was a plan MANDATED by Obama administration? Not a bad concept in keeping supply chain easy to to get parts and to keep cost down...... just trade off ... being mandated; made it harder to go back to custom parts (like armor) cause it was not anywhere in the commercial realm.

You're about 30 years off on your timeline. Obama took office in 2009. The FMTV prototype contract was awarded to S&S and Teledyne in 1988 for 15 prototypes each. S&S got the manufacturing contract in 1991 and the first FMTV's were fielded to the Army in 1996.

If any "administration" was involved it would have been the Reagan Administration.

The whole body armor and armored support vehicle media backlash that cause the Pentagon to mandate everything be armored was around 2006 during the G. W. Bush administration. That's when they started building everything custom and expensive. Now they have recently brought back the HMMWV under a refurbishment contract because the JLTV is just too over the top and expensive for many basic roles.

 

[coachgeo]

Your about 30 years off on your timeline. Obama took office in 2009. The FMTV prototype contract was awarded to S&S and Teledyne in 1988 for 15 prototypes. S&S got the manufacturing contract in 1991 and the first FMTV's were fielded to the Army in 1996.

If any "administration" was involved it would have been the Reagan Administration.

The whole body armor and armored support vehicle media backlash that cause the Pentagon to mandate everything be armored was around 2006 during the G. W. Bush administration. That's when they started building everything custom and expensive. Now they have recently brought back the HMMWV under a refurbishment contract because the JLTV is just too over the top and expensive for many basic roles.

somewhere the PDF on the complete decision to go to the commercial part designs is out there. Have read it. Doc. was not in the 80's. Though it may have started back then and not become "mandated" till later. Pretty sure the Doc. is early 90's. Not sure when it became mandated though. Good point though... If mandated in 90's your right.. that still is not Obama years.