repower options for M123 tractor

[maddawg308]

I have a buddy west of here who isn't on Steel Soldiers, he owns a M123 tractor, one of the early ones with the LeRoi gas motor in it. The truck is in nice shape, but the motor suffered a detonation many years ago, so there is a hole in the block, and the rest of the motor got scavenged for parts over the years to keep other LeRoi motors in operation. He would like to do a repower of the truck and asked me what options there were out there. I know the NHC-250 from the -809 series 5-tons would fit easily, but would have the same output as a 5-ton sized truck, actually less since it would have to move more weight. I'm not sure if a NTC-400 would fit in the -123 bay.

Can anyone shed some light of potential options for a repower? He'd like to use the tractor only for offroad purposes, hauling heavy equipment around, or for bringing to a couple local MV shows (yes, he knows the rig is too wide for road use with the duals on).

 

[gimpyrobb]

If one were going to waste their time putting a nhc250 in, a 6CTA should fit and have lots of power.

 

[jrobinson5093]

I vote for 3408 cat but thats just me. But if a NHC 250 will fit then a BC400 will, they are very similar in size.

 

[NDT]

The Cummins 855 CID inline 6 engines are too long. The engine compartment is not much bigger than a mulitfuel 5 ton. He is looking at great complexity attempting to mate a newer engine to the Mack transmission/transfer unit. I would say find another LeRoi, the surplus dealers will be happy to be rid of them.

 

[maddawg308]

The Cummins 855 CID inline 6 engines are too long. The engine compartment is not much bigger than a mulitfuel 5 ton. He is looking at great complexity attempting to mate a newer engine to the Mack transmission/transfer unit. I would say find another LeRoi, the surplus dealers will be happy to be rid of them.

Sources for the LeRoi engines would be appreciated, and I'd pass them on.

He is willing, I should say, to yank the existing tranny unit and replace with whatever works best, even an automatic.

 

[wreckerman893]

If I remember correctly, and I may not, didn't some of them have either the 903 Cummins V-8's or the 318 Detroits in them?

 

[TacticalTruck]

It was a 300 Cummins. They do not have a divorced T-case. The trans/transfer is one unit. I would guess its a standard SAE bell housing that would allow an engine swap.

 

[doghead]

Why doesn't he join the site himself, so he can get first hand info.

 

[NDT]

Sources for the LeRoi engines would be appreciated, and I'd pass them on.

Sam Winer Motors shows to have some.

 

[maddawg308]

Why doesn't he join the site himself, so he can get first hand info.

Old fart (well, Frank is olDER), no computer and no desire to learn how to use one. All the info about rallies and upcoming events I have to pass along to him, if he doesn't learn it through MV mag. Why, DH, you don't trust me to act as a suitable ambassador of SS to others?

 

[maddawg308]

Sam Winer Motors shows to have some.

Many thanks, will pass it along.

 

[Merc1973]

Pics, or you know what...

 

[maddawg308]

Of course, I go out his way in a couple weeks, I'll snag some pictures while I'm there.

 

[wreckerman893]

The M123 suffers from the same deficiency as all the other tank haulers the Army ever bought. They are gearbound to around 45 MPH. My guess it to keep young soldiers from committing mayhem on the public roads with large trucks carrying heavy loads.
It would be interesting to see if putting 1600x20's on one would give it a few more MPH.
They were also horrendously underpowered, first with the huge gas burner, then a boat anchor Cummins diesel and maybe with the 318 Detroit (I swear I have seen a M123 with a double breasted Yamaha in it).

If it could be shoehorned into the engine compartment a 3406B model Cat would be the ticket. Put a 13 speed behind the kitty cat and call it good.

 

[SteveKuhn]

Today is the 1st I've noticed this thread, and my 1st thought was: "HolyMoly!!! He's finally gone round the bend on a truck for Rausch Creek!"

Back to previously scheduled intelligent re-engineering.

Steve

 

[M813A1]

Well the Cummins NHC 250 or Big 400 are to long to fit the engine bay of the M123 He might consider a Cummins V903 possibly a 3208 CAT or the 318 Detroit they should fit that engine bay OK ????

 

[Castle Bravo]

...It would be interesting to see if putting 1600x20's on one would give it a few more MPH...

16.00x20s are about the same size as 14.00x24s, if not nominally a little bit shorter.

 

[Dirt71]

opcorn:

 

[AMGeneral]

Ok,since I didn't see it posted yet,there is one further problem with the inline 6(except for the 8.3C ) they are all limited to 2350 to 2450 rpm MAX,whereas the V8-300 in the M123 and the Le-Roi are both governed at 3000 and 2800 rpm respectively.

Just something to consider in the engine swap as well.

 

[WillWagner]

DURAMAX!! An LBZ.