Yuba Steam Engines,

All Wheel Drive Tractor, Engine and Boat Motor

 

The All Wheel Drive Tractor

   
     
    Yuba Tractor
   

Lothrop & West, A Discription of "Yuba Steam Vehicles" (paper)

(Click on a picture for a larger view, then enlarge it further with your browser.)

Yuba Steam Vehicle   Yuba Steam All-Wheel Drive Tractor

Side view

 

Bob Harns Driving, Pulling a Compactor

     

Yuba All-Wheel Drive Tractor

 

Yuba Tractor Drivers Position

Bob Driving, Pulling a Compactor

 

Driver's Position

Yuba Steam Vehicle   Yuba Steam Vehicle

Rear Knee Action Suspension Transverse Leaf Springs

 

Right Front Engine

Yuba Steam Vehicle

 

Yuba Steam Vehicle

Turning to left

 

Turning a Tight Circle

Yuba Steam Vehicle   Yuba Steam Vehicle

Disappearing into the sunset

 

Bob in cross wise position turning front wheels from full left to full right

Yuba Steam Vehicle  

Excerpt from Lothrop & West's Yuba Steam Vehicles

The Yuba -tractor was built as an experimental, proto¬≠type vehicle between about 1946 and 1951 by a small group at Yuba Manufacturing Company, San Francisco and Benicia, California, as a possible successor to the "Ball Tread" crawler tractors manufactured by Yuba in the early teens. The new tractor work started from scratch with ideas and sketches, clay and wood models and machine drawings, one unit of the vehicle at a time, to carry out the special concept of an on-road and off-road, earthmover style tractor on pneumatic tires with four-wheel drive and propelled by steam. (Auxiliaries were powered by a Jeep 4 cylinder engine.) Reliance was placed upon the earlier Doble work, but there were many changes from most past practices.  Read more.......

Bob Harns and the Yuba Tractor

   
Yuba Steam Vehicle   Yuba Steam Vehicle

Backing in to cross wise position

 

Coming in to narrow alley at Yuba Benicia plant

     

Yuba Steam Vehicle

 

Yuba Steam Vehicle

Right front engine and right front Kuse action and 90 deg steering rods   Yuba Tractor Rear Elevation
 
 

Back to Top


Yuba Tractor Engine

     
     
Yuba Tractor Engine   Yuba Tractor Engine

Excerpt from LOTHROP & WEST: A surviving engine from the destroyed tractor has recently (1975) been used for laboratory testing at Steam Power Systems, San Diego, at even higher temperatures and with good results.

Yuba Tractor Engine   Yuba Tractor Engine
     
Yuba Tractor Engine   Yuba Tractor Engine
     
Yuba Tractor Engine   Yuba Tractor and Marcus and Athel Lothrop 1951
Marcus and Athel Lothrop driving the Yuba Tractor.
   

Back to Top

 

Yuba Boat Motor

Excerpt from LOTHROP & WEST: In addition, a very light, portable, complete plant of about 10 horsepower was built for boat propulsion. This system was about as described (as the Yuba Tractor) except for scale. A battery driven electric motor took the place of the "Jeep” engine. The condensers were under water, as was the steam engine. That had three cylinders in line with an overhead cam shaft. There was a similar valve shifting mechanism with one forward cutoff and one reverse cutoff.

     

Yuba Boat Motor

 

Yuba Boat Engine Steam Generator and Stack

Bob Harns and the Yuba Boat Motor

 

Boat Steam Engine and Condensers on its Side

     
Bob Harns and the Yuba Boat Motor   Bob Harns and the Yuba Boat Motor

Boat Engine Mounting and Intermediate Frame Tank Structure

 

Yuba Boat Engine Steam Generator and Stack

Yuba Boat Engine Steam Generator and Stack   Yuba Boat Engine Steam Generator and Stack

Engine Held by Polite Workman

 

Pistons and Connecting Rods

     

Yuba Boat Engine Steam Generator and Stack

 

Yuba Boat Engine Steam Generator and Stack

Generator Burner and Control Unit

 

Generator and Elevation and Control Unit

Bob Harns and the Yuba Boat Motor   Yuba Boat Engine Steam Generator and Stack
Yuba Boat Motor Frame and Etc.   Engine Generator and Flex Hose

 

 

Back to Top