Gravely 20-G
The Gravely 20-G is a tractor produced by Gravely Lawn Tractors. It is equipped with a 770 cc 46.98 ci engine. The listed engine power is Gasoline (gross): 20 hp / 14.9 kW. Transmission: 8 forward and 4 reverse. Operating weight: 883 lbs 400 kg.
Engine Power
Gasoline (gross): 20 hp / 14.9 kW
Fuel & Capacities
5.3 gal
20.1 L
Transmission
8 forward and 4 reverse
Operating Weight
883 lbs
400 kg
Overview
 | 1988 - 2001
Model year 1988-19981999-2001
Professional G SeriesGarden tractor
Professional G Series
Garden tractor |
|---|
Production | |
|---|---|
Manufacturer | Gravely |
Garden tractor | |
Gravely 20-G Engine | |
|---|---|
20HP Kohler 770cc 2-cyl gasoline | |
Fuel tank | 5.3 gal
20.1 L |
Engine details ...  | |
Gravely 20-G Transmission | |
|---|---|
8-speed gear | |
Transmission details ...  |
Mechanical | |
|---|---|
Two-wheel drive | |
Manual steering | |
Mechanical band brakes | |
Open operator station. |
Dimensions & Tires | |
|---|---|
Wheelbase | 52.3 inches
132 cm |
Weight | 883 lbs
400 kg |
Front tire | 16x7.50-8 |
Rear tire | 23x10.50-12 |
Full dimensions and tires ...  | |
Electrical | |
|---|---|
Ground | negative |
Charging amps | 15 |
Battery volts | 12 |
Battery AH | 42 |
Battery Group | 22F |
References | |
|---|---|
 | |
Riding Tractors published in 1990, by Gravely | |
Riding Tractors published in 1991, by Gravely | |
Riding Tractors published in 1998, by Gravely | |
Operator's Manual G Series (53213) published in 1992 | |
Service Manual Professional-G Series (26793B) |
Engine
Engine Detail — 770 cc / 46.98 ci Gasoline
Manufacturer | Kohler M20S |
Fuel Type | Gasoline |
Configuration | 2-cylinder, air-cooled |
Displacement | 770 cc
46.98 ci |
Bore/Stroke | 3.125x3.062 inches
79 x 78 mm |
Power (gross) | 20 hp
14.9 kW |
Rated RPM | 3300 |
Starter | electric |
Starter volts | 12 |
Oil capacity | 1.5 qts
1.4 L |
Transmission
Transmission — 8 forward and 4 reverse shaft-driven gear
Type | shaft-driven gear |
Gears | 8 forward and 4 reverse |
Oil capacity | 6 qts
5.7 L |
Oil type | SC10W-30 |
 | |
SC10W-30 |
|---|
Dimensions
Gravely 20-G Tires | |
|---|---|
Lawn/turf front | 16x7.50-8 |
Lawn/turf rear | 23x10.50-12 |
Dimensions | |
|---|---|
Wheelbase | 52.3 inches
132 cm |
Length | 82 inches
208 cm |
Width | 43.2 inches
109 cm |
Height | 51 inches
129 cm |
Weight | 883 lbs
400 kg |
Attachments
Attachment overview | |
|---|---|
50" mid-mount mower deck | |
60" 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. |
Photos
Gravely 20-G
Recommended Implements & Sizing Guide
Engineering recommendations for Gravely Lawn Tractors Gravely 20-G based on its 20 HP power envelope and ASAE agricultural standards.
| Implement & Operation | Recommended Size | Workload Rating | Engineering Notes |
|---|---|---|---|
Moldboard PlowPrimary Tillage | 1 to 2 Bottom (12")1 - 2 铧 (30 cm) | Light Duty | Ideal for garden plots and light sandy soil. |
Rotary Cutter / MowerMowing & Clearing | 4 ft (48 in)1.2 m | Light Duty | Pasture clipping and light brush under 1" diameter. |
Rotary TillerSeedbed Prep | 42 to 48 in105 - 120 cm | Light Duty | Covers compact tractor tire width. |
Disc HarrowSecondary Tillage | 5 to 6 ft (16-18" discs)1.5 - 1.8 m (40-45 cm 耙片) | Light Duty | Small acreage soil break-up and secondary aeration. |
Sizing & Soil Condition NoteActual implement sizing varies depending on local soil conditions (heavy clay vs sandy loam), field slope, and operating speed. Heavy tillage implements may require front ballast weights and wheel weights.
Fluids, Capacities & Working Autonomy
Standard fluid requirements, service intervals, and continuous runtime estimates for Gravely Lawn Tractors Gravely 20-G.
Estimated Continuous Field Runtime: 5.1 hrs
Approximately 5.1 hours of continuous field operation at ~75% rated power on a full tank (5.3 gal / 20.1 L).
Estimated 75% Load Fuel Burn~1 gal/hr (3.9 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
Gravely Lawn Tractors Gravely 20-G Specification Unit Converter
Convert power, fluid capacities, and operating weights between metric and imperial standards for Gravely Lawn Tractors Gravely 20-G.
Converted Equivalents:
Horsepower (HP)20 hp
Kilowatts (kW)14.9 kW
Metric Horsepower (PS / CV)20.3 PS
Direct Competitor Comparison
Compare Gravely 20-G against same-era industry alternatives in the same horsepower class.
Current Model
Gravely Lawn Tractors
Gravely 20-G
Engine Power:Gasoline (gross): 20 hp / 14.9 kW
★ Baseline Reference
International HarvesterMarket Competitor
International Harvester 184 Lo-Boy
Engine Power:18
Production Years:1977 - 1980
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