Designation No.7a
Bore 1 inch
Stroke 1 inch
Configuration Vertical single cylinder
Height 7 1/2 inches
Extra equipment Drain cocks
Displacement lubricator
Reversing gear
Taps required 4, 5, 7 BA
5/32, 3/16 x 40 tpi
1/4 x 32 tpi
1/4, 7/16 x 26 tpi
Notes The vertical version of the No.8, these two engines make up a larger version of the 10V/10H pair of engines. There is an obvious family resemblance in all four engines with their trunkguide crosshead and overall proportions.