Bolens 3012G ST125
The Bolens 3012G ST125 is a tractor produced by Bolens Lawn Tractors. It is equipped with a 655 cc 40 ci engine. The listed engine power is Gasoline (gross): 12.5 hp / 9.3 kW. Transmission: Peerless 801.
Engine Power
Gasoline (gross): 12.5 hp / 9.3 kW
Fuel & Capacities
5 gal
18.9 L
Transmission
Peerless 801
Overview
![]() | 1986 - 1987
Suburban SeriesGarden tractor
Suburban Series
Garden tractor |
|---|
Production | |
|---|---|
Manufacturer | Bolens |
Garden tractor | |
Built in Port Washington, Wisconsin, USA | |
Variants | |
|---|---|
3012G | gear |
3012H | hydrostatic |
Bolens 3012G Engine | |
|---|---|
12.5HP Briggs & Stratton 655cc 2-cyl gasoline | |
Fuel tank | 5 gal
18.9 L |
Engine details ... | |
Bolens 3012G Transmission | |
|---|---|
5-speed gear | |
Transmission details ... |
Mechanical | |
|---|---|
Two-wheel drive | |
Manual steering | |
Disc brakes | |
Open operator station. |
Power Take-off (PTO) | |
|---|---|
Mid PTO | independent |
Clutch | electric |
Dimensions & Tires | |
|---|---|
Wheelbase | 45 inches
114 cm |
Front tire | 15x6.00-6 |
Rear tire | 20x8.00-10 |
Full dimensions and tires ... | |
Electrical | |
|---|---|
Ground | negative |
Battery volts | 12 |
Battery AH | 45 |
References | |
|---|---|
![]() | |
High Performance published in 1987, by Bolens |
Engine
Engine Detail — 655 cc / 40 ci Gasoline
Manufacturer | Briggs & Stratton 404707 |
Fuel Type | Gasoline |
Configuration | 2-cylinder, air-cooled vertical-shaft horizontally-opposed |
Displacement | 655 cc
40 ci |
Bore/Stroke | 3.44x2.16 inches
87 x 55 mm |
Power (gross) | 12.5 hp
9.3 kW |
Starter | electric |
Starter volts | 12 |
Oil capacity | 1.5 qts
1.4 L |
Transmission
Transmission — Peerless 801
Transmission | Peerless 801 |
Type | belt-driven gear |
Gears | 5 forward and 1 reverse |
![]() | |
Dimensions
Bolens 3012G Tires | |
|---|---|
Lawn/turf front | 15x6.00-6 |
Lawn/turf rear | 20x8.00-10 |
Dimensions | |
|---|---|
Wheelbase | 45 inches
114 cm |
Length | 69 inches
175 cm |
Width | 34.5 inches
87 cm |
Height | 42.5 inches
107 cm |
Attachments
Attachment overview | |
|---|---|
36" mid-mount mower deck | |
Snowblower | |
Blade | |
Garden tractors are capable of using tillers, plows, or other ground-engaging attachments. TractorData does not list details of these attachments. |
36" Mower deck | |
|---|---|
Type | mid-mount Bolens |
2-blade | |
Cutting width | 36 inches
91 cm |
Photos
Fluids, Capacities & Working Autonomy
Standard fluid requirements, service intervals, and continuous runtime estimates for Bolens Lawn Tractors Bolens 3012G ST125.
Estimated Continuous Field Runtime: 7.7 hrs
Approximately 7.7 hours of continuous field operation at ~75% rated power on a full tank (5 gal / 18.9 L).
Estimated 75% Load Fuel Burn~0.7 gal/hr (2.5 L/hr)
Engine Crankcase Oil
SAE 15W-40 (Heavy Duty Diesel)
Standard Spec: API CK-4 / CJ-4 Heavy Duty
Service Interval: 150 – 250 Hours
Transmission & Hydraulic System
UTTO (Universal Tractor Transmission Oil)
Standard Spec: ISO VG 46 / 68 (Wet Brake & Trans Compatible)
Service Interval: 600 – 1000 Hours
Engine Cooling System
50/50 Ethylene Glycol Pre-mix
Standard Spec: ASTM D6210 / Heavy-Duty OAT Antifreeze
Service Interval: 2 Years / 1500 Hours
Bolens Lawn Tractors Bolens 3012G ST125 Specification Unit Converter
Convert power, fluid capacities, and operating weights between metric and imperial standards for Bolens Lawn Tractors Bolens 3012G ST125.
Converted Equivalents:
Horsepower (HP)12.5 hp
Kilowatts (kW)9.3 kW
Metric Horsepower (PS / CV)12.7 PS
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