Replacing your multifuel engine with something else? - Steel Soldiers::Military Vehicles Supersite

wolfmangk · 07-03-2007, 22:14

I was talking to a farmer the other day who has the Hercules LD-465 engine (Diesel only, though) in a tractor. He says the Cummins engine in the new Dodges will do the same amount of work and use half the fuel.

I was talking to the guy who is giving me the M35 (Who says I cannot be pulled over if I am driving a military vehicle

) and he says the Cummins and the Continental are apples and oranges...

He states that the Cummins is a high RPM engine, and the Continental is a low RPM engine. He says you CAN put the Cummins in, but you'd blow it up because it is a high rpm engine. (???)

Let's say it was viable-and you'd get 15 MPG or more, or less-what about the bellhousing? What about the electronics, etc-it seems like it'd be a tremendous undertaking.

P.S. This gentleman says that if you remove the governor the M35 will do 90 MPH.

WillWagner · 07-03-2007, 22:22

The Cummins B is a 2500 rated engine, 2800 in a Dodge. Don't know if the LD and the LDT are different, but the LDT is rated at 2600 RPM. The B actually makes OK power at 1400 RPM, but make peak power at 2500. If you remove the governer on ANY diesel engine, they will run faster...RPM = speed...for how long, who knows. There are flywheel housings available for the B that will bolt right up to the trans in a deuce Yes, you can still get pulled over in a mil.veh.

CatMan · 07-04-2007, 01:51

Guy's,

I can't stand it - I have to jump in here. Yer talking about stuff that just ain't so.

All the engines in this size will operate in the 2100 to 2900 RPM range. There are lots of different ratings for different arrangmnets. Match the size of the engine to the equipment.

The Cummins B series is a 5.9 (call it 6) Liter engine.
The LDT465 is a 7.5 Liter engine
The Cummins C series is an 8.3 Liter
The Cat 3126 is a 7.2 Liter
The old Cat 3208 is a 10 Liter

The Cummins B is too small for this application. In the early 1990's Cummins bought the old Southeastern Surplus yard in Agusta Ga and renamed it Cummins Military Systems (CMS) - With the intent to remanufacture M35's for oversea export customers which they did in considerable numbers. But with the Cummins C series engine. Cat sold the 3126 for the M35A3 upgrade - Service Life Extention Program (SLEP) They both fit fine.

Side note: Cummins junked hundreds and hundreds of WWII vehicles from that yard to "clean it up" but that's another story.

One of the neatest M35 repowers I've ever seen is the installation of a rebuilt Cat 3208. The short wide Vee 8 fits well and provides more displacement and higher horse power and will operate all day long at 2800 RPM. Sorry I didn't meet the owner but it was East Coast

http://i137.photobucket.com/albums/q...08CatinM35.jpg

For the money, I'd stick with the LDT465 engine. Next choice would be go find an old 1980's County Highway truck with a 3208 with an SAE number 3 rear housing and a flywheel for a manual transmission. Rebuild that and repower. It's a simple rugged engine that had a 30 year life span.

And don't ever let someone tell you that you can "remove" the governor from a diesel engine and operate it. On a gas engine with a carb, a governor is an add on devise to limit top speed. With a diesel, it must have a governor to control the fuel. Start a diesel without a governor and it will immedietly go into uncontroled overspeed until it gets what we call "the come aparts". Some people call it a "runaway" but that's more what the mechanic does when it overspeeds.

Much easier to keep it stock and you can't beat the sound of the M35 Turbo.

Cat Man

steelsoldiers · 07-04-2007, 05:23

Wolfman, both of those fellas you talked to are a little wacky. The first thing you need to do is spend a couple of long nights reading posts in the deuce forum and the deuce modding forum. There have been Cummins and CAT swap write-ups posted. You will also find that the deuce in it's stock engine form, is a very reliable truck. The LD-465, LDT-465 1C/1D engines may be considered under-powered by today's standards, but they were matched carefully to the truck and won't snap u-joints, break input shafts, etc... Once you start adding more power and bigger tires, you run the risk of breaking something downstream or at least causing greater wear on components. Running 70 mph in a 13k lb truck with 30 year old NDT tires with stock brakes and manual steering is not my idea of a good time and can be a risky proposition. Drive your deuce with the stock multi-fuel for a while and enjoy it.

CatMan, being that you are brand new here, you wouldn't realize that Will is a diesel truck technician with lots of experience on a great variety of medium duty and class 8 trucks. He wasn't actually saying it was OK to run a diesel without a governor. It's hard to perceive sarcasm in print. While you wouldn't want to remove or disable the governor, it is perfectly acceptable to modify it to change the RPM limits. The P7100 pump in the 5.9 6BT in my Dodge and in the 8.3 CTA in my 923A2 has 2 springs with set screws to control the RPM limit. The 3000 rpm springs will open up the top end very nicely. The 4000 rpm set are used more by the pullers and racers. You have to install heavier valve springs with the 4000 rpm set up to prevent float.

If you search you will find some excellent posts on SS about engine swaps in a deuce. Both the Cummins 5.9 and the CAT 3208 have been used successfully. In the M35A3 you mentioned, sure the 3126 fit between the frame-rails just fine, but once they added the tranny cooler, the inter-cooler, the radiator, the PS cooler, etc... they ended up with some Frankenstein hood that was chopped apart, lengthened, widened and pop-riveted back together with sheet-metal.

I agree that folks should stay out of the injection pump if they don't know what they are doing. Disabling the governor doesn't make sense.

I'm a diesel nut and love to tweak them for more power, but I really enjoyed driving my completely stock LD-465 powered M35A2. It had plenty of low-RPM grunt and sounded great too!

m-35tom · 07-04-2007, 09:40

90 mph is 4014 rpm. i don't see it happening for more than a few minutes...............

Recovry4x4 · 07-04-2007, 10:25

Hmm, the b series cummins too small? You might need to tell Charles Talbert at M Series Rebuild. He does these rebuilds for a living and gets great results. HRD has one in his deuce with 16:00X20 tires and it runs great he reports. Says it runs much better than the multi that was in there and it had propane injection. There are at least 2 folks here with 3208 powered deuces in addition to the one if the picture which was built by m-35tom who posted above. As far as CMS, it used to be Commercial Military Systems when Thomas Coder ran the place, wasn't aware of any Cummins buyout. WillWagner, whats the weight on an 8.3CTA? Gotta be quite heavy for a deuce which is within a few hundred pounds of the front tire weight limit with just the multi and a winch.

area52 · 07-04-2007, 10:26

Quote:

Originally Posted by CatMan

Guy's,

I can't stand it - I have to jump in here. Yer talking about stuff that just ain't so.

The Cummins B is too small for this application.

Cat Man

The Cummins B engine is NOT too small, with proper adjustments, it can easily put out 300hp and over 600 ft-lbs torque. these are common engines and replacement parts are not that hard to find.

I plan on repowering my M292A2 van with a Cummins 5,9 as soon as that pot o' gold lands at my feet

Westech · 07-04-2007, 11:05

hey I run my M35 at 2900 RPM at well over 60 mph and she drive like a dearm. Now chris is right on the power to the truck... its low because when that truck is loaded (or over loaded to the hills) you really dont want 500 hp and a thousand foot pounds. The Multi make well more then enough power to twist every single drive shaft and brake every axle in Low Range. If you want to move something the Deuce WILL move it! just not a light speed. I will never replace my Multi... after the 800 mile day this year at WOT 2900 rpm towing a M1008... how can you go wrong. Im sold on a Multi

WillWagner · 07-04-2007, 11:18

From the book,

Automotive

Bore....................114 mm [4.49 in]
Stroke....................135 mm [5.32 in]
Displacement....................8.27 liters [504.7 C.I.D.]
Engine Weight (dry) with Standard Accessories....................603 to 612 kg [1330 to 1350 lb]
Wet Weight....................635 to 658 kg [1400 to 1450 lb]
Firing Order....................1-5-3-6-2-4
Valve Clearances:
Intake....................0.30 mm [0.012 in]
Exhaust....................0.61 mm [0.024 in]
Rotation, Viewed from the Front of the Engine....................Clockwise
Compression Ratio:
6C8.3....................16.4:1
6CT8.3....................17.3:1
6CTA8.3....................16.5:1
C8.3....................17.3:1 (low torque) or 18:1 (high torque)

I'll bet the LDT would get real quiet and smooth up at 4000!

CatMan, Welcome to Steel Soldiers!

Cummins is still on a "clean it up" kick I had to stop the little bean counters from disposing of some of the tools we have made over the years because they didn't "look like tools" to them....donkeys! Do you have any noisy, smelly green iron? if so,

Recovry4x4 · 07-04-2007, 13:42

Wow, the 8.3 is surprisingly light. Multis weigh more than that.