Gray Motor
Company
Detroit
Michigan
Two
Stroke Marine
Engines
To determine the year manufactured
1. Find Serial number: on makers plate or Stamped on flywheel or cylinder casting.
2.Disregard last three numbers, fourth number is year manufactured.
To determine the
decade of manufacture, the physical properties of engine have to
be considered .
1. --1906 First engines on market, these were made by DuBrie Engine Co.( serial no's different than GRAY).
2. --1907- 08 First actual engines manufactured by Gray
models "R" and "S". one and two cylinders 3-12 HP.
3. -- 1911-12 Change from gib key to tapered shaft and nut at flywheel.
4. -- 1912 "U" Model added to line
5. -- 1914-15 No more oilers. model "S' not in catalog . water pumps still on front of engine
driven by the timer shaft. Model "T" added to the line. Mississippi Sandsucker a 6hp
model "R" with large aft mounted piston waterpump is in catalog.
6. -- 1916 By this time the waterpumps are on the rear of the engine, and are a piston pump
driven by an eccentric on the output shaft. The model "U' has flat bolt down plates as
inspection covers.
7. -- 1917-18-19 Not much change ( WW I ) and starting factory again.
8. -- 1920 Model "U" Has round threaded inspection covers.
9.-- 1927 Two cycle engine production ceases.
These are guidelines and any catalog or other information that can adjust or add to
this list is
welcome.
Engine
List
Model
Year Serial
No.
Notes
Owner
DuBrie
1..-----1906--07 1396
First engines sold by GRAY
Ernie
Darrow
Gray
"R"
1.---- 1907 16R7673 Early eng, spoked wheel (possible
stationary)
Al (Rustyal)
2.----- 1911 10R11145 10 Hp single Richard Durgee
3.----- 1912 06R2922 Oiler and Gear Box Bill schaller
4.----- 1913 06D3649 Twin Richard Durgee
5----- 1913. 16R13817 Gray Carburetor Bill Schaller
6.----- 1920 010s724 Incomplete Bill Schaller
"S"
1.----- 1911
S11453
Single
Miro Forest
2.----- 1913 06D3642 6 hp George Coates
"T"
1.----- 1920
124T20863
Twin
Bill Schaller
"U"
1. ---- 1912 23012024 Very early, excellent condition Ernie Darrow
2.----- 1914 26U14333 Twin Nick Bettevy
3.----- 1918 3U28714 Single Randy Ryderbush
4.----- 1921 23U11698 Twin Nick Bettevy
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