Bowser-Stewart Logo _stewart
HO - Freight Cars
HO - English's Freight Cars
HO - Steam Loco Kits
   PRR & Other Docksides
   PRR A-5 Shifter
   PRR B-6 Switcher
   PRR H-9 Consolidation
   PRR L-1 Mikado
   PRR I-1 Decapod
   PRR K-4 Pacific
   PRR T-1 Duplex
   PRR E-6 Atlantic
   PRR & LIRR G-5
   PRR M-1 Mountain
   PRR M-1a Mountain
   USRA & PRR N2s
   USRA Mountain
   USRA Light Mikado
   USRA Light Pacific
   NYC K11 Pacific
   UP Challenger
   UP Big Boy
   Old Lady Consolidation
   Casey Jones
HO - Stewart Diesels
HO - Trolley Cars
HO - Turntables
HO - Trucks & Tenders
HO - Repair Manual
HO - Cal Scale
HO - Cary Loco Works
HO - Selley Castings
HO - DCC Information
HO - Can Motor Kits
HO - Kit Builder's Tips
HO - Aero Train
HO - Mechanisms for
   Bachmann Locos

Penn State & Big Ten
N Scale Cars
O Scale Products
S Scale Products
Z Scale Cars

On-Line Catalog
About Us
navigation bar

Bowser - HO - Steam Loco Kits
PRR M1 Mountain 4-8-2

History:  The M-1 was a single prototype model 4-8-2 that was designed and produced by Juniata in 1923. This model was locomotive 4700, shop construction No. 3819. After two years of testing and road trials, the M-1 was approved for fleet construction.

M-1 designers, W. F. Kiesel, Jr. and J. T. Wallis transplanted features from the I-1s decapods. They allowed for a larger combustion chamber, but left most of the other features unchanged. Other items borrowed from the I-1s included the following: guides, crossheads, and various machinery parts. Some special features of the M-1's were: pilot deck-mounted air resevoir tank, 27" x 30" cylinders, 72-inch drivers, medium sized tenders, 250 pounds of boiler pressure, KW type trailing truck, Belpaire firebox, small steel cab, a total weight of 385,000 pounds, and could haul a load of up to 64,550 pounds.

The original engine was built with a very small tender and no mechanical stoker. It was hand fired, which led to great difficulties in handling this massive machine. Stokers and larger tenders were soon implemented.

Mountains were the first classes of superheated power to drop the "s" from class designation. All engines were superheated by this time, so the "s" was no longer needed.

"Mountains" are so-named because they were considered big and powerful for such work when first designed during World War I. These were considered to be the best steam locomotives the railroad ever owned; they replaced the Mikados, Decapods, and Santa Fe's. They became known as "the hallmark of Pennsy fast freight service".

Complete Kit and Accessories:  The locomotive and tender complete kit has all of the parts to build a working model. You may wish to add your own details or purchase our "Super Detail Kit" if available. Some models have an optional painted engineer and fireman, smoke unit kit and other assemblies available as optional equipment to compliment your kit-building needs.

Kit Components and Replacement Parts:  The following parts are listed in order to identify parts in your kit or to replace parts that have been lost, damaged or simply worn out.  This is not a complete list of all of the individual parts available for this model - please call Bowser with your specific requirements if you cannot find the parts you need.  You may also use our on-line catalog to find parts by description.  Please note that part numbers with a price of "Call Us" may be part of an assembly and may not be available as a separate purchase item.

  Cylinders 27" x 30"
  Firebox 125-15/16" x 79-7/8"
  Steam pressure 250 lbs.
  Tractive force 64,550 lbs.
  Engine weight-working order 382,400 lbs.
  Engine weight on lead truck 59,300 lbs.
  Engine weight on drivers 266,500 lbs.
  Engine weight on trailing trks. 56,600 lbs.
  Weight of tender, loaded 217,900 lbs.
  Length with Tender 12-3/8"
  Weight 2 lbs 6 oz.
  Minimum radius 22"
  Power Bowser DC-71
  Drivers 72"
  Color Brunswick Green

Assembly- Exploded View Drawings
(click on any image to enlarge)
Boiler & Mechanism Boiler

Photographs of Super Detailed Model
Photo 1 Photo 2 Photo 3 Photo 4 Photo 5 Photo 6
Photo 7 Photo 8 Photo 9 Photo 10 Photo 11

Prototype Photgraphs
Photo 1 Photo 2

Page Footer Image