Hall-Scott’s legendary 1090 cubic inch OHC six cylinder gas engines were the most powerful truck engines in their day, making up to 310 hp on butane (LPG) at a time when diesels were struggling to hit 150 hp. But even that wasn’t enough for this owner-operator of a tank hauler who wanted to tear up the Western mountain grades as fast or faster than coming down. So he requested that Kenworth build him a new truck with a mammoth V12 from Hall-Scott, essentially two of those big 1090 cubic inch sixes on one crankcase, an engine designed for marine or industrial use. Kenworth had to lengthen the hood by a foot to accommodate it, but they made it happen.
In this shot we see the happy owner in the cab taking delivery of his new 600 horsepower hot rod Kenworth, along with a field rep from H-S (left) and a Kenworth sales rep. Unfortunately, the smiles didn’t last very long, but not for the truck’s lack of pulling power on those mountain grades. And it wasn’t the fuel bill either.
In the definitive—and only—book on the history of Hall Scott, there’s this picture with a caption that suggests they were considering offering the big OHC hemi-head V12 as a truck engine, but there’s nothing more in the text, including its hp rating. These V12s were rated at up to 900 hp, but that was with a supercharger, as used on some WW2 military high speed boat applications. I did find a reference to a caption for the top picture—but no longer available on the web—that stated this particular engine was rated at 600 hp, which sounds about right, given the 300 hp rating of the one-half sized six.
Torque would have been a staggering 1900 ft-lbs, based on double the 950 ft-lbs rating of the half-sized six.
This is the other photo in that book, taken at the same time as the top photo. The caption isn’t quite correct, as apparently Kenworth did the installation.
So why didn’t the owner’s smile last long? Apparently the rig went up in flames, and was a total write-off. No details were given. Hopefully it was only the tractor and not the load of fuel in the trailer(s).
Update: a commenter left a copy of an industry article on this rig, and according to it this turns out to be a 1948 Kenworth and its engine was destroked to 1870 cubic inches and its power reduced to 450 hp since no driveline components could handle the higher torque of the 2181 cubic inch Defender V12.
What a history! Thanks. The old truck salesman never heard of this bit of hauling. Love it. When I was representing Cummins Diesels, we had a customer in The Bronx on 138th Street – Gerosa Hauling – who had a monster Mack with a Cummins V-1710. It was used for some serious heavy hauling.
Man, Gerosa is a name from the past, along with Perillo. The last few years I lived in New York I worked for an equipment rental company in White Plains and saw those trucks all the time. On a related note another outfit had an Autocar with a Detroit 12V-71 that made an awesome noise accelerating.
We were much more humble, our “big” truck was a Ford Louisville and most work was done with 6.9 IDI diesel F350 dualies.
The Detroit engine would get scared when it saw a hill the Cummings engine climbs a whole lot easier and faster
Must not be a driver…I’ve driven Cummins, and DD15 I’ll take the DD15 all day long.
Can’t compare a dd15 or series 60 to an old 671 or 8v71, back then even the 53 series was used in trucks.
Run water with an s2500 international with a silver 6v-92ta. Never ran the ol 2 strokes before but had always heard they were piles.
Was nothing but impressed tbh. Little sluggish on the top end but a monster out of the whole.
Pulls 80k lbs Like any 330hp motor should
They always said that a Detroit was like a teenage girl. Talked real pretty in town, but when you got her out in the country, she wouldn’t put out.
Hello! Do you know anything about this model?
Thank you!
The most powerful truck ever (to that time) – and it burned itself up? That sounds like the old fable about the guy who made wings to fly, but flew too close to the sun and everything went bad from there.
It would have been great to read about how the rig spent 20 years hauling the heaviest of loads up the mountains, passing slower traffic left and right. But this powerhouse going up in flames is almost as good of an ending to the story.
Icarius the Liability?
Possible insurance job?
This rig must’ve been crazy expensive. Perhaps the owner fell on hard times?
Just sayin’… 😉
I’d be surprised if it wasn’t an insurance job. Who could afford to run it and who would buy it?
You tailor the truck to the job its doing fuel is the cheapest thing you’ll ever buy for a working vehicle, breakdown callouts are the killer and towing even worse.
You got that all wrong, which is a bit surprising (or not) given that you’re a truck driver. Fuel is by far the highest operational cost of trucking, accounting for 39% of the total. Second is labor cost (driver), which makes up 26%. The purchase/lease cost is 17%. Repairs and maintenance: 10%. Insurance: 4%. Tires: 3%. Permits, tolls and licenses: 2%.
Given the significantly higher fuel cost in NZ, I would assume fuel is even a higher percentage there.
Not to speak for Bryce, but I took the comment to say that breakdown (and the lost revenue that results) is the highest cost. Your list of out-of-pocket expenses looks reasonable, but that list omits business losses/disruptions which show up elsewhere in the financials.
The costs you cite all balance against the revenue that the truck generates, which has to be greater than 100% of the out-of-pocket running costs (if the trucking company is to remain in business, anyway). When the truck is not generating revenue, that loss is necessarily greater than any of the operating expenses.
Dont forget the chicken lights. Lol
It all depends on where the truck’s home base is.
Percentage of total operational costs:
Western Europe: 38% labor costs, 27% fuel.
Eastern Europe: 22% labor costs, 37% fuel.
Source: https://www.nt.nl/wegvervoer/2021/03/31/kostenkloof-oost-en-west-europa-blijft-in-stand/?gdpr=accept
Your list of out-of-pocket expenses looks reasonable, but that list omits business losses/disruptions which show up elsewhere in the financials.
I assume it’s included in repairs and maintenance.
FWIW, in the modern trucking industry, “breakdowns” and the resulting loss of revenue are minuscule. Modern trucks, like modern cars, are extremely reliable, and operators manage their fleets very carefully, turning them over at the point where reliability might possibly become an issue.
I don’t have the numbers at hand, but my educated guess is that breakdowns and resulting revenue loss is well below 1%. It did not even show up on that breakout of main trucking industry costs I quoted from.
He said that ” fuel is the cheapest thing you’ll ever buy for a working vehicle”. That was the main thing I was disputing.
Update: here’s that 2020 trucking industry cost report. There’s no doubt in my mind that breakdowns are included in repairs and maintenance. If it were a significant different line item, it would be shown as such.
https://truckingresearch.org/wp-content/uploads/2020/11/ATRI-Operational-Costs-of-Trucking-2020.pdf
No, breakdowns, maintenance etc ARE a huge part of operating costs. Fuel, tires electrical etc etc etc. I’m an Owner Op for many years. Even a new truck will suffer these costs…guaranteed!
New trucks breakdown 100 times more than trucks 2007 and older!!! And that’s a fact!! Truck breakdowns and unreliability of new emission motors is the biggest cause of trucking companies that have folded up in the last 10 years! I own a truck and trailer repair business and I know this first hand.
When the truck is not generating revenue, that loss is necessarily greater than any of the operating expenses.
And the sun comes up in the morning.
Seriously, Jim, this is a bit silly, due to being so utterly obvious. But it says nothing, as the only question is, how often does that happen? The statistics suggest that it’s so infrequent that it doesn’t even merit being a separate line item. (I’ve just perused a number of detailed trucking financial reports).
Scott: According to the American Research Institute’s 2020 report of costs, Repairs and Maintenance averaged $0.143 per mile, or 8.6% of the total costs of $1.652 per mile. This report is the industry gold standard:
https://truckingresearch.org/wp-content/uploads/2020/11/ATRI-Operational-Costs-of-Trucking-2020.pdf
Some drivers have reported going over ten years or more without a roadside breakdown.
Icarus.
There’s no 1/4 mile figure, because the nose already reached the finish from the startline.
How incredibly magnificent, both to behold as an object and to contemplate as a working tool. Thank god for slightly crazy people like Mr Western Mountains Flattener, they make the world better.
HALL-SCOTT engine =
Power
Glorious sound
Unquenchable thirst .
-Nate
Perhaps this truck is only road vehicle in existence that the driver could actually watch the fuel tank needle moving to the E faster than he could accelerate from the standstill…
I am curious about the fuel consumption this truck got.
1900ftlbs of torque is right up there with modern diesels the T610 I drove for a month had 1950ftlbs the maximum the 18 speed ultrashift Eaton Fuller could reliably cope with, @58,000kgs/127000lbs fully laden powered up steep hills traction even loaded being the only real problem, empty on the return run was interesting to say the least, accelerating away from cars uphill was fun but the wheelspin warning light would come on and stay that way wet roads were insane and thats using modern tyre technology in 1951 this must have been an absolute beast of a truck, I like it.
I would say that this truck was probably rated in gallons per mile. The exhaust pipes must have been glowin red hot under a pull up the hill.
P.S., don’t stand too close to the air intake.
The Hall-Scott V 12
Power for the steepest grade
Never pulling over
What a piece of engineering!
I find it doubly interesting because of the LPG fuel. I love LPG due to its simplicity, octane and general cleanliness.
I also wonder of the LPG system was the cause of fire of said truck’s demise. This can easily happen with a poor installation.
I don’t see much for fuel tanks on this thing, You would need some good size tanks to get any range with this monster.
I read about this truck awhile back and it stated this truck was involved in a accident when it burned
My dad got on with Los Angeles County fire in the late 60’s. He told a story of driving a twin turbo Hall Scott in a fire truck. LA county fire also had two special made Crown Coach buses with 500 inch Hall Scotts laying horizontally for hauling people around, usually cadets. Uncle Mike remembers riding in one to go out for oilfield training. Years later one was found and restored. I have been lucky enough to get to drive it a bit, what a connection as my dad spoke of driving them also.
There were no turbocharged Hall-Scott engines, but they were plenty fast enough. Crown coaches with underfloor H-S engines were very common, although many were re-powered with Cummins diesels later.
Perhaps Erik meant supercharged. According to this rather fascinating link they built over 400 of those in WW2. Just 900HP!
https://usautoindustryworldwartwo.com/hall-scott.htm
Those 482 some supercharged Defender V12s built during WW2 for Navy use were the only production supercharged H-S engines ever built. They required a number of modifications to handle that extra power.
Given that H-S was California-based, their engines were extremely common in fire trucks there; they were almost universal for pumpers in LA and other cities for decades, as pumping is just about the ultimate test of output. But these were all six cylinder 400/440 series engines (or successors) making some 275-300 hp, which was quite exceptional at the time.
I’ve gone back to my copy of “Hall-Scott, The Untold Story Of A Great American Engine Maker” and it appears that they did build a small number of a turbocharged and fuel injected version of the 400 six, only for the military, specifically for some high-output applications like snow blowers.. Called the model 442, 159 were built.
There’s also a reference to a 1956 6182 GT engine, also fuel injected and turbocharged, but there is no remaining evidence of it actually having gone into production. It appears to have been a development engine, but for one reason or another, was not built.
By 1956, the move to diesels was growing, and the demand for gas engines falling, so presumably H-S did not see a market big enough for it.
Instead, they designed and built a diesel engine, but that turned out to be a dud, which pretty much was the death knell for H-S.
Is it theoretically possible that one of those military turbo 442 found its way into a fire engine. Yes. But the odds are very much against it, as fire departments did not tinker with their expensive equipment, as reliability was absolutely paramount.
My Dad was with the San Diego Fire Dept. from 1956 to 1976 & they too had several pieces of apparatus powered by Hall Scott engines. Dad loved ’em-they’d pump for days-all ya had to do was feed them. Very advanced engines for their time.
If this hadn’t burned up, wow!
Great post. I can remember the ground vibrating when walking past Crown coaches with just the big H-S six. I can imagine the tremblor this would cause…
The second picture of the truck looks like it has a temporary gasoline tank mounted on the frame behind the cab. LPG conversions were often done by an upfitter after the truck was manufactured. It doesn’t have a 5th. wheel hitch either, so that is likely how it left Kenworth.
The truck was built for an Oul Jobber from Elgin, Oregon USA. A small town in North Eastern Oregon.
He wanted to pass busses going East with a load up what is now I-84 grade referred to as Cabbage by most people. 6 miles of 6 percent is the current grade. I’ve driven the Old Highway and it is a little longer and comes in at the same summit.
There is another route that is a little shorter into Elgin but requires crossing a thousand foot higher summit.
The truck was built as a Body load tank chassis with a 2nd trailer behind it. Fuel was plumbed directly from the truck tank through a 1/4″ fuel line. A likely point of the fire.
I don’t know much more about it. The American Historical Truck Society had an article about it around 2010 (give or take a little).
Great article that much HP in 1950 would have been something. Just think no A/C no power steering no Jake Brake you worked to earn make a living
I my. Dads garage, I recalled him working on a bus with a hall Scott engine Midway on the bus, under the bus, laying on its side.
Its not 1951 kenworth but 1948 kenworth and the engine was derated to 1870 cu.in. from original 2181 cu.in. so the horsepower was derated from 600hp to 450hp because no drivelines or axle that could handle that kind of power. Also, the article shown rare picture of the truck with its own tanker and trailers
Thanks for that. I was not able to find any reliable sources of information on this rig and its engine. I will update the article.
I worked at an independent truck repair shop in Seattle. In the mid seventies I was sent on a service call to the local truck shop that had acquired a IH west coaster tractor with a 1090 Hall Scott. Get it running— that was the work order. It had sat for some years. I had never seen anything like it, having worked on mostly diesels. I filed the points and cleaned the carbs and the fuel tanks. With a fresh battery it fired right up and was so quiet compared with the diesels I could hardly believe it was running. Bobtail back to the shop it had amazing power. Just shift the main box. Who needs the brownie?
Ended up here after listening to C.W. McCall’s Wolf Creek Pass. CW started the story with a load of chickens coming out of Wiggins.
One of the lyrics mentioned sound of starting a 1k cubic engine in a 1948 Pete, which woke up the chickens. I wanted to learn more about this song,
It’s a pretty funny old song, but I was mainly interested in that 1k cube. Anyone know which engine CW was singing about?
I just got back from the boat show at the Antique Boat Museum in Clayton NY where a Hall Scott Defender was one of the items in the annual auction the Museum holds. 4100 lbs of mostly cast iron! Apparently used in the WW2 63′ rescue boats. Very interesting listening to some of the antique engine guys I know talk about it and the the related Hall Scott Invaders. It was purchased by one of the founders/owners of Gar Wood custom boats. He’s not sure what he will do with it, but for $250 it will make an interesting conversation piece ( and also saved a historical engine from the scrapyard)!
I’m kind of curious as to why KW didn’t offer a more reliable 12V-71 Detroit. They should have been well established in production by then and the HP rating would have been close to 600 in a naturally aspirated model.