Medium Kit – Box and Shaft

Designed for the 13-16hp single-cylinder small engine. 100” Longtail Shaft (1-piece). Kit weight totals 44 lbs. Best used on boats with a 42” bottom or less. Saltwater ready.

The DIY Medium Kit was designed for the 13hp Predator 420cc and the 15.8hp Predator 459cc engines.

Parts List:
- 8” prop & 8.5” prop
- 100”, 1-piece, Longtail Shaft
- Coupler Housing & Coupler PTO Shaft
- Engine Base, Transom Bracket, and Tiller Handle
- Grip, Throttle Lever, and Stainless Throttle Cable
- Kill Switch with Adapter, Mounting Hardware, and Decals

This kit will fit the Predator 420cc engine and the Predator 459cc engine, along with numerous other engines if they meet the requirements below:

Engine base bolt pattern: 7.72” x 3.7” 196mm x 94mm
Engine side cover bolt pattern: 5”(127mm) Diameter with 4 x 5/16 – 24 UNF
Engine PTO Shaft diameter of 1”
Engine Weight: Less than 81-lbs

If paired with a Predator 420cc engine (73-lbs), the total weight of the kit and engine would be approximately 117-lbs, and little to no experience will be needed when it comes to dialing in this kit for easy handling. There are no confusing adjustments when it comes to balancing or tailweight. It is pre-balanced and designed to be used with a 13-15 hp engine that weighs less than 81-lbs. It's meant to be simple and ready to run straight out of the box.

Coupler Housing - The coupler housing is made of solid steel and requires no additional bracing. There is a single grease zerk located on the top for easy maintenance. Hand-friendly wing bolts are used at the end of the coupler housing to secure the long tail shaft in place (just in case you forget your crescent wrench).

Coupler Shaft - A shaft machined from a single piece of steel for increased strength and durability. Allen set screws are used to secure the coupler shaft to the engine PTO shaft and to secure the key in place. Allen set screws are used instead of bolts because they help maintain balance and decrease potential vibration.

Longtail Shaft - The longtail shaft is an 100” shaft of 1-piece construction. Our long-tail shafts use bushings made from a specific hardwood that doesn't swell in water. We prefer wood bushings because they work extremely well. With adequate maintenance and use, the hardwood takes in and expels the grease as needed and provides an ideal environment for a steel shaft spinning at 3600 revolutions per minute. The wood works symbiotically with the grease and water to maintain shaft alignment and temperature. When it comes to shaft bushings, heat from friction is the number one cause of wear and failure. If wood is overheated, there is one thing wood doesn’t do… melt. Some companies claim that a “polymer” bushing is superior to a wood bushing. If a polymer bushing gets too hot (not maintained or greased enough, or not enough water flow) the bushing will melt, leaving you stranded. With proper maintenance, our wood bushings are extremely durable, and will last for many years.

Engine Base - Left or Right-handed operation. A cutout to allow for easy oil changes. Made with .25” thick powder-coated steel. Designed simple to achieve a longtail that handles easily with no complexity.

Transom Bracket - Not too big, not too small. Made with .2” thick stamped, powder-coated steel. Fits on transoms up to 2.3” thick with pads and jam nut installed. If the nut is removed, 2.5” may be achieved. Utilizing two hand-friendly wing bolts equipped with a transom pad and locking nut on each, enables you to install and secure your bracket to the transom with confidence and ease.

Tiller Handle - The tiller handle is bent in a way so that it can be operated comfortably while standing or sitting. It also has adjustment holes for securing it in position if you which to angle your tiller handle a certain way.

Throttle Lever - This lever is made from machined aluminum which allows it to be lightweight and rust-free. It also has an above-average cable pull, providing full travel of the engine throttle from idle to full open throttle.

Throttle Cable - The throttle cable provided is a 10-strand twisted stainless steel inner cable 72” in length with a 67” outer shield. One end has a barrel, while the other end is cut and welded.

Handle Grip - A comfortable grip is also provided for the end of the tiller handle. These things last years in the sun without showing wear.

Safety Kill Switch - The kill switch is water resistant and built to last through the weather and beating that a mud motor owner is going to put it through. An adapter is also supplied to allow for easy installation of your engine. All you need is a wire stripper and a crimping tool to complete the installation.

Props - The kit comes with a 8” and 8.5” prop. These are standard high-quality aluminum props. The 8” would be used in situations with a heavy payload. The 8.5” is for light payloads and speed.

Customer Feedback - https://diymudmotors.com/diy-mud-motor-kit-reviews/ 

In the end, you end up with a simple, lightweight kit that is designed to be an affordable workhorse and provide you with years of dependable use.