Mount a Direct Drive System to the Engine with the Direct Drive Alternator Bracket
Custom bracket to mount a direct drive system to the engine. Two-piece set will fit all engines with bolt circles up to 7.5 inches. Spacers and bolts not included. The engine plate has mounting slots such that it can fit all engines with bolt circles smaller or equal to 7.5 inches. This covers everything from 3 HP to 20 HP. The plate with the large hole is where the alternator mounts.
There are spacers and bolts connecting the two plates. We do not provide the bolts or spacer tubes. The engine plate comes with nuts pre-welded to the side of the plate that faces away from the engine. This is done so that the surface of the plate that touches the motor is free of obstructions. The spacer tubes need to be large enough in diameter that they can sit over the nuts (the nuts sit inside the tubes). In the example shown, we used square tube for the spacers but we have also used 3/4 electrical conduit for the spacers. The length of the bolts and the length of the spacers must be determined at the time of assembly and are not provided.
Bracket Details
- Made from 10 gauge steel (0.135" thick)
- Available in Bare Steel (no finish)
Optional Items
- 1/2" Direct Drive Coupler
- 5/8" Direct Drive Coupler
- 3/4" Direct Drive Coupler (for most 5 HP and smaller shaft motors)
- 7/8" Direct Drive Coupler (use with most vertical shaft motors)
- 1" Direct Drive Coupler (use with 8 HP horizontal motors and others)
- Special Alternator Coupler (special threaded and counter bored for GM alternators) — Custom made to direct drive GM alternators with Gas engine
- Spider Insert for all couplers — One spider required for each pair of drive couplers
Additional Information
Q: How do you direct drive a generator head with an engine?
A: With the direct drive shaft coupler assembly.
To connect the output shaft of an engine to a generator head input shaft (or anything else for that matter), a special shaft coupler is required. Basically, three pieces are needed.
Select a coupler half that is the correct size to fit the engine shaft (or driving shaft size), then select a coupler half that is the correct size for the generator head (or driven shaft size). Then the two shaft couplers are joined using what is called a spider. Notice that the shaft couplers each have 3 fingers and the spider has 6 slots. The three fingers from the engine side fit into three of the spider slots, and the three fingers from the generator side coupler fit into the other three slots on the spider. This coupler assembly allows for several degrees of misalignment between the two shafts and protect the bearings from seeing side loads that would result from misalignment.
The Special Direct Drive Alternator Coupler is custom machined to replace the nut, lock washer and pulley on a standard GM 10si alternator.With this, and our direct drive bracket set you can build an ultra compact and reliable charging system with no belts to wear out.
Installing our Custom Direct Drive Alternator Coupler
We have had a few customers ask for the easy way is to install our custom direct drive alternator coupler. First you have to remove the nut, lock washer and pulley from the alternator. The only practical way is to block the fan on top of a piece of wood, and use an air impact wrench on the nut. If you don't have one, take your alternator to any shop and pay them a few dollars to do it for you.
Now, to install our alternator coupler you will need an Allen wrench to fit the end of your alternator shaft, and a second one goes across 2 of the ears. Hold the shaft in position with the center Allen wrench, and turn the coupler with the other wrench as shown. Again we will install this for you on request.