John Deere 420 Garden tractor built in Horicon, Wisconsin. The John Deere 420 is powered by a two-cylinder, 20-horsepower engine. The tractor can reach a top speed of 15 mph. It has power steering and hydraulic brakes and a three-point hitch for attaching implements. The PTO aka Power Take Off system has two forward speeds and reverse.
Available attaches for the John Deere 420 include loader buckets, backhoes, mower decks, snowblowers, front-end loaders, plows, and rakes.
When it was first released in 1983, the John Deere 420 cost around $6,489. The B48G was the original engine on the Deere 420, used through the 1986 model year. It is a 781cc gasoline 2-cylinder air-cooled horizontal-shaft opposed-twin engine. It is Two-wheel drive.
Engine
Onan B48G or Onan P220G
- 20HP Onan 782cc 2-cyl gasoline (781.64cc 47.7 cu in)
The Onan P220G engine had more horsepower compared to the Onan B48G engine. Here are the specifications for both:
Onan B48G: This engine typically produced around 18 to 20 horsepower. (The version for the 420 should have 20hp) Onan P220G: This engine produced around 20 horsepower.
The Onan B48G in the John Deere 420 model was tuned to produce 20 horsepower. For the 1984 John Deere Lawn and Garden Tractors, the typical engine used was indeed the Onan B48G. This engine was commonly found in the John Deere 318 model, which was a popular lawn and garden tractor during that time. While the 318 model had 2 less horse power than the version for the 420, the B48G engine was produced in different variants with slight modifications that could result in varying horsepower ratings.
The Onan P220G was also used in later years. John Deere switched to the Onan P220G engine for their lawn and garden tractors starting in 1987. The mounting points for the P220G should align with those of the B48G. The P220G benefited from a more modern design and engineering enhancements that improved overall durability and efficiency.
Onan P220G Improvements
- enhanced cooling system design for better heat dissipation
- an upgraded ignition system, providing more reliable starting
- improved fuel efficiency
- lower emissions due to improved combustion efficiency
- quieter engine, lower vibration, more serviceable design
Onan B48G
This is a two cylinder air-cooled four-stroke small gasoline engine with horizontal shaft manufactured by Onan for John Deere. The Onan B48G is a popular engine used in a variety of applications, from lawn mowers to small tractors. It has an L-head design with two flat cylinders; a carburetor fuel system, an automotive-type battery ignition system, and an electric starter.
A service manual was available from Onan, labeled the "Onan Service Manual B43M and B48M Engine."
Operators Manual Versions
- Operators Manual 316, 318 and 420 Lawn and Garden Tractors (OM-M72236) published in 1986
- Operators Manual 316, 318 and 420 Lawn and Garden Tractors (OM-M79655) published in 1989
- Operator's Manual 316, 318 and 420 Lawn and Garden Tractors (OM-M87709) published in 1984
- Technical Manual 316, 318 and 420 Lawn and Garden Tractors (TM1590) published in 1995
420 Serial Number Groups
- 1983 M00420X222001
- 1984 M00420X285001
- 1985 M00420X315001
- 1986 M00420X360001
- 1987 M00420X420001
- 1988 M00420X475001
- 1989 M00420X595001
- 1990 M00420X010001
- 1991 M00420X100001