Collection: DIY Horizontal Shaft Belt Drive Generator

Build your own AC/DC Generator with a Horizontal Shaft Gas Engine with one of our Universal Horizontal Mounting Brackets

Add a DC to AC power converter, and you have a super high output DC charging system, as well as an AC generator. Detailed information on this project and be f"ound on our Blog at Convert A Lawn Mower into a Generator - Horizontal Mount (Part 1).

Convert a lawnmower engine to create a HORIZONTAL shaft belt drive generator. We have designed and manufactured a simple, one piece universal mounting bracket specifically for this task!

Two bracket sizes are available for this project (LONG and SHORT versions).

Universal Horizontal Shaft Generator Bracket

Unique bracket mounts a 10SI or 12SI GM alternator to a horizontal shaft gas engine to create an AC/DC generator. The simple way to build your own generator! We have designed and manufactured a simple, one piece universal mounting bracket specifically for this task! This bracket bolts to the motor (using a universal bolt pattern), and allows the alternator to bolt directly to the bracket. The bracket also has an integral belt adjustment slot which allows the alternator position to be adjusted, which serves to tension the belt.

The Universal Horizontal Mounting Bracket is designed for the small footprint GM 10SI or 12SI Alternator. Larger alternators will not fit!

Bracket Dimensions - LONG Version Horizontal Shaft Long Mounting Bracket

19.5" long x 8" tall
13" from center of motor shaft to center of alternator shaft with belt adjusted in center
6.6" between standard 2 bolt mounting bolts for GM 10si alternator
Made from 10 gauge Steel or Stainless Steel (0.135" thick)

Optional Items for the Long Mounting Bracket

4" Pulley for Engine (Cast Iron, 3/4" engine shaft)
37" Belt (use with 4" pulley on motor and 2.5" alternator pulley)

Bracket Dimensions - SHORT Version Horizontal Shaft Short Mounting Bracket

16.5" long x 8" tall
9" from center of motor shaft to center of alternator shaft with belt adjusted in center
6.6" between standard 2 bolt mounting bolts for GM 10si alternator
Made from 10 gauge Steel or Stainless Steel (0.135" thick)

Optional Items for the Short Mounting Bracket

4" Pulley for Engine (Cast Iron, 3/4" engine shaft)
28" Belt (use with 4" pulley on motor and 2.5" alternator pulley)

Related Items

Alternators and Regulators

Refurbished Alternator For use with any of our generator projects. If you plan to run your system near capacity for extended periods of time, we recommend replacing the standard pulley on the alternator with one of our special Industrial "A" belt alternator pulleys above.

Be aware, you must have a battery hooked up to an alternator or you will damage the internal voltage regulator if you try to rotate it at normal RPMs.

Alternator Pulleys

If you plan to run your system near capacity for extended periods of time, we recommend replacing the standard pulley on the alternator with one of our Special Industrial "A" belt alternator pulleys.

We offer a special 2.5-inch Industrial "A" style pulley that fits the GM 10SI and 12SI alternator. This special pulley will fit any of the alternators we sell, and we will install it for you at no cost by special request. If you already have your own alternator, or did not buy an alternator from us, we cannot guarantee this pulley will fit your alternator. You may return it if it doesn't work out, but you will be responsible for shipping costs BOTH ways which may be more than the cost of the pulley.

Alternator Direction and Fans

An alternator will function in either direction. Cooling can be an issue, however the fan still functions (but at reduced efficiency). The alternators in our projects are bolted to a metal mounting plate which acts as a large heat sink. We do offer a special bi-directional fan that can be used in place of the stock fan. This fan is as efficient when rotated in either direction.

Alternator Fan A bi-directional fan is available from us! For a true reverse direction fan, you will find them used on '65–'69 Corvairs. But the Corvair fans have an integral pulley which cannot be removed and is not the ideal diameter. Bi-directional fans for use with our 10SI and 12SI GM alternators are available here at TheEpicenter.com. If you already have an alternator, we cannot guarantee these will fit. They will only fit if the existing fan has a dish in the center, and the dish points toward the alternator.

NOTE: We no longer offer or provide technical support for Propane Conversions or Propane Conversion Kits. Please contact U.S. Carburetion Inc. in West Virginia.