Many of the readership will identify the name Carco as being associated with logging winches and forestry equipment. However, Carco’s roots go much further back in history to the dawn of the track-type tractor. By Richard Campbell
Originally founded in 1905 in Seattle, Washington, Carco (originally known as the Seattle Car Company) set up a manufacturing facility in 1908 in Renton, a town not far from Seattle.
Renton, incidentally, is also the home of Aerospace giant Boeing, at one point the largest manufacturer of commercial airliners in the world.
At first the Company manufactured railway wagons and minor bits & pieces of logging equipment.
However, not long after setting up shop in Renton, the fledgling Company merged with the Twohy Brothers of Portland, Oregon, also manufacturing the same kind of gear and renamed the venture the Pacific Car and Foundry company.
Their primary business remained the manufacture of railway cars, chokers, cable, hooks, and logging trailers up until 1934 when the first powered logging winches were introduced.
In order to provide a full line of equipment for the budding tractor owner, Carco also ventured into the manufacture of bulldozer blades.
While a little crude at first, the Company soon got the hang of it and began producing both cable and hydraulically operated models, primarily to suit Allis-Chalmers and Cletrac tractors, although with some adaptation, these would also fit International-Harvester and Caterpillar tractors.
The logging trailers also gave way to specialized logging arches in several different sizes with tracks supplied by the Trackson Company of Milwaukee, Wisconsin (later to become part of Caterpillar).
Carco had a fair bit of competition in the early years from other logging oriented firms such as Isaacson, Young, Braden, Gearmatic and its biggest rival, Willamette-Hyster (later Hyster) who were also based on the Pacific west coast.
In an ironic twist, both Braden and Gearmatic would be purchased in later years by Pacific Car & Foundry.
Carco became a “preferred supplier” to Allis-Chalmers in 1937 and Cletrac in 1938.
These agreements mainly involved the supply of logging winches as Allis-Chalmers in particular, already had contracts in place with both Baker and GarWood for the supply of bulldozer blades.
Carco’s bulldozer blades were available in three basic models – straight, tilting and angledozer, and two methods of operation, cable or hydraulic.
In either case, the Company built the entire unit, frame, blade and hydraulic pump or cable winch as appropriate.
Most cable-controlled equipment was powered with a single drum Model L Power Control Unit (PCU).
The Model L was quite versatile in that it could be either front or rear mounted on the tractor as circumstances dictated.
Many users jettisoned the Model L when it came due for overhaul with a more suitable replacement.
Carco did not venture into twin drum PCUs or trailed tools such as scrapers, rippers or compaction equipment, correctly deducing that these fields were already well served by other manufacturers.
It was quite a surprise then when it entered the field of dozing equipment, a market already heavily laden with competitors.
The Cable Dozer Blades
Carco cable operated bulldozer blades could be mounted in two ways – front lift or track lift configuration.
Front lift blades had a fabricated frame mounted directly to the chassis and up over the radiator guard in a similar fashion to LeTourneau.
While LeTourneau’s frames were squared off, Carco’s featured a graceful arch to which the lifting sheaves were attached.
These frames did not have the overhead “headache bar” common to other manufacturers and featured the PCU in front of the radiator, driven off the crankshaft.
No cable passed over the operator’s head.
A suitable guard was furnished to keep material from entering the PCU.
Track lift cable blades had all the necessary lifting framework mounted on the machines track frames with the cable control PCU always at the rear.
This system was very similar to Bucyrus-Erie’s and must have raised a few eyebrows in the Bucyrus’ patent copyright department!
Be it front lift or track lift, Carco mounted the dozer blade push arms pivot point directly over the recipient tractors drive sprocket.
Knowing the limitations of early metallurgy, this must have caused all sorts of problems in service when the blade hit an “immovable object” and transferred the shock stress directly into the sprocket drive.
Repeated stress of this type was known to spread the track frames on International TD-18s equipped with the Bucyrus frame blade and is almost certain to have done the same to Carco blade equipped tractors.
This was known in the trade as “ducks disease”!
The Hydraulic Dozer Blades
All of Carco’s hydraulic dozer blades were track frame mounted and, without exception, always had the hydraulic pump located at the front of the tractor behind the radiator guard and driven directly off the machines crankshaft.
Its design was very reminiscent of LaPlant-Choate, Kay-Brunner and Bucyrus-Erie types although no patent infringement lawsuits seemed to have occurred.
Blade down pressure was somewhat limited due to the state of hydraulic technology of the day, and was more reliant on blade weight and good moldboard curvature.
Carco ceased production of all its dozer blades following the end of WWII.
This was due to several factors, one of which was Allis-Chalmers aligning itself even more closely with GarWood and Baker and the fact that some of the big manufacturers such as Caterpillar were beginning to make their own attachments.
To find a Carco blade still fitted to an old tractor these days is a rare thing.
Carco also manufactured a range of clearing blades which could be attached to other manufacturer’s C-frames or blade arms.
In New Zealand we would call them brush rakes and it was the last dozer related item that Carco manufactured, lasting well into the late 70s.
It would be remiss of me not to mention the basic core business of Carco, and that was logging winches.
These were manufactured in many sizes and produced to fit every known make of track type tractor produced in the USA.
From forestry to pipelining, you either had a Hyster or Carco winch – that was it.
Carco winches had an extremely good reputation for strength and reliability.
Models such as the F, G and J are legendary and remained in production virtually unchanged for many years, testament to their success.
For a time it was very popular (and still is in some places) to skid multiple logs under an arch.
The arch provides the benefit of lifting the load off the ground for less resistance, allowing more logs to be pulled than by normal skidding.
It is also the same principle as modern log skidders use.
Most of Carco’s range of arches were track mounted to provide less rolling resistance due to lower ground pressure and also, they were immune to tyre punctures as with other brands.
The log arch seemed to fall from favour in the early 1970s and was quietly dropped from the marketing catalogue.
Over the years, Pacific Car diversified its interests into other areas, their first major acquisition being Kenworth Trucks in 1945.
This was followed not long after by Kenworth’s construction division, K-W Dart.
These days PACCAR International, as Pacific Car and Foundry came to be known, is a massive organization incorporating Peterbilt, Kenworth and DAF trucks but still manufacturing logging winches.
The New Zealand Connection
It is difficult to tell if any Carco dozer blades came into New Zealand.
Your author has never seen one but that is not to say that some didn’t get imported as several manufacturers were also offering Carco’s winches as attachments.
There have been many winches and log arches of Carco manufacture used in New Zealand forests,
For the Model Collector
You are well out of luck trying to find Carco products attached to diecast models.
There is only a J series winch on the back of one of Spec Cast’s International TD-24’s but the tractor is towing an Isaacson arch.
There are no known scale models of Carco dozer blades in existence.