Todays Yanky iron Fix

...that DEW Line vid showing the Kenny's and their fuel tank location may be one key to this unusual early rig we are all pondering over....

...another problem with dating the pic is the fact it has the individual letter sets....that was a late 50's /early 60's style of Kenworth badging in the US (idstbc)

individual letters began in 1950
first bullnose was 49 and still had oblong kenworth plate with ribs 1950 got letters as did the conventionals
rids around the back of the cab ran till as late as 59
as the used up stock

jim nvhb1 is the 1486 cube v12 naturally asperated made 400hp nvtb twin turbo 500hp

those dew line macks are 1710 v12 5 1/2 bore
which weren't built till 1961

I'm pretty sure the pic was taken at the Kenworth factory around 1955.
I was looking at the air cleaner, if it had a Hall-Scott engine wouldn't it be on the other side? Also it goes into the side of the bonnet quite low down, which might be ok for the intake on this supercharged Cummins. They were using LeRoi engines around this time too, maybe a 844cu in petrol V8?
The Kenworth model 803 dumptruck had a 400hp 1486cu in V12 engine

Thanks for your input Grandad... One thing we know for sure if you believe the plate on the hood is it has a Cummins Diesel of some description,and yes I was thinking a NVHBI-1200 which was fitted in a Kenworth 803 during the mid 50s (what does the 1200 mean???) and it is definately a 1950s build going by the rear view mirror as well as other features already pointed out by Detective and Binder.
Sorry Detective but Binder just got one up on you... lol.I was wondering how long it would take some-one to notice the fuel tank behind the cab....
I just want you guys to know I'm not out to prove anyone right or wrong,this truck definately got my eye the moment I saw the photo and I have no idea what model Cummins.But would love to know..... JOTS.

Don't think that is part of that truck Hayseed, I think it is in the background.

Probably a Dumb Question,

However :
WTF is the Scoop looking gadget sticking up out of the LHS of the big hood. (below the air horn of the truck in the background)..

jim hrb 600 was the model # for the 6 cyclinder 743 cube cummins and the v12 was basicly 2 hrb600,s joined together so hvb1 1200

grandad that pic is a pretty rare cummins
first of the supercharged h models
2 valve head intake and exhaust on the right side
4 7/8 bore 672 cube
I have only seen one in a 48 sterling
thanks for posting it

....well i haven't had a guess at what Cummins engine may be in the AFL banger....but i reckon i might have a crack and suggest it could be a very early experimental application of the 855 cubic inch 14 litre Cummins in an over-the-road unit.....

....they were dimensionally a much bigger engine than the 743 cu/in and from what i understand these bigger engines were being offered in off-highway trucks from around 1959....

... the bonnet length looks reasonable in this light, and the wide front might have been precautionary ...a brand new engine application may have mandated the use of additional/excess cooling capabilities till the unknowns were known...(a bit like our first conventional Aussie 900 series Kenworths with their wide fronts...but otherwise they were a very standard spec)...

...the very early over-the-road 855's could be specced up to 335 HP (NT335) and the off road units were up to 420 and running higher industrial application revs (2350 rpm +)...

....that's my take on it....all makes perfect sense....probably all wrong too : :.....cheers fellas

external dimentions of 743 and 855 are identical 855 cube nh series engines 5 1/2 bore internal fuel lines
were first introduced in 1961!5-10 years after this truck
hp was nh 250 natural aspirated
ntc 270 turbo non piston cooled
ntc335 turbo piston cooled
nta 380 piston cooled and some had a aftercooler in the
intake manifold which was the same as the manifold on the 500 hp small bore v12s mainly industrial engines

69-70 855 went to ffc block [handbag w/pump]
and parallel nose crank plus a bunch of smaller changes

hp was
ntc 290 turbo piston cooled no after cooler
ntc350 as above but aftercooled
nt400 as above
nta 420 with remote mount w/pump

nta420 was the roadtrain engine of choice back then
co ord , red north, rta john bain, all had them

these were the most common there were many variations ntct 270 927 cube supa 250 to name a few

and all these engines were governed at 2100 rpm!!!!!

so binder as you seem to no a lot more than about cummins than me is the 743 a HB series motor and an 855 NHB series ? as I have a HB 600 motor but couldnt get sleaves for it or pistons as it was a smaller bore 4 and 7/8 I believe so I just replaced it with a 6 71 GM not quite the same

...the NT series of turbo engines were the earliest...with lower compression and different valve timing compared to the NTC (custom torque) range of engines that came along in the mid 1960's...

...NT 280's and NT335's (with no piston cooling) were the pioneers in over-the-highway Cummins turbo rigs!!!

...the NTA was an industrial engine with higher RPM and a far more shallow torque curve, and completely unsuited to automotive applications!!!

...i did mention ''experimental'' for the pictured Kenny, as i just don't believe they would have chucked these engines in and said "off you go" !!!!!