Horizontal Crankshaft


Ready for almost anything. Low noise levels and emissions with plenty of power and reliability.

Horizontal Crankshaft

Reliability meets Intelligence

GX120 Specifications
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Dimensions diagrams


Common model dimensions illustrated above. Model specific dimensions available in the "Downloads" menu.

Performance Curve



Engine Type Air-cooled 4-stroke OHV
Bore x Stroke 60 mm x 42 mm
Displacement 118 cm3
Net Power Output* 3.5 HP (2.6 kW) @ 3,600 rpm
Net Torque 5.4 lb-ft (7.3 Nm) @ 2,500 rpm
PTO Shaft Rotation Counterclockwise (from PTO shaft side)
Compression Ratio 8.5:1
Fuel Tank Capacity 2.0 litres (2.1 U.S. qts)
Lamp/Charge coil options 25W, 50W
Carburetor Butterfly
Ignition System Transistorized magneto
Starting System Recoil
Lubrication System Splash
Governor System Mechanical
Air Cleaner Dual element
Oil Capacity 0.56 litres (0.59 U.S. qts)
Fuel Unleaded 86 octane or higher
Dry Weight 13.0 kg (29 lbs.)


Length (min) 297 mm (11.7”)
Width (min) 346 mm (13.6”)
Height (min) 329 mm (13.0”)

PTO Shaft Options

A2 type N/A
AR type Rammer
B type N/A
D type N/A
E type N/A
H type N/A
K type N/A
L type Reduction type PTO
N1 type N/A
N5 type N/A
N7 type N/A
P type N/A
Q type Straight shaft
R type N/A
S type Straight shaft (metric)
S3 type N/A
T type Straight shaft
V type N/A

*The power rating of the engine indicated in this document is the net power output tested on a production engine for the engine model and measured in accordance with SAE J1349 at 3,600 rpm (net power) and at 2,500 rpm (max net torque). Mass production engines may vary from this value. Actual power output for the engine installed in the final machine will vary depending on numerous factors, including the operating speed of the engine in application, environmental conditions, maintenance, and other variables.

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