Shaft Shark
AB Marine is pleased to offer the Shaft Shark propeller protection device.
You may download a PDF version of the brochure at the bottom of this page.
What is a SHAFT SHARK?
The SHAFT SHARK is a serrated edge circular blade … machined from high quality (316L) type stainless steel. It is available as a split 2 x piece unit for quick and simple installation. Also available as a single piece unit for larger shafts.
What does it do?
Attached to your shaft just forward of your propeller, it rotates with the shaft, cutting away any rope, weed or debris that might try to entangle your shaft & propeller.
Why do I need one?
• To keep your propeller free from rope, weeds and underwater debris.
• Eliminate the possibility of damage to your shaft, propeller and strut.
• Eliminate the need for being towed due to fouled stern gear or propeller.
How do I choose the right model?
• Supply the shaft diameter on your boat either standard SAE (inch) or metric.
• Supply the diameter of the fwd end of your propeller hub.
Installation:
Models #300, #400 & #500 are split units and so installation is simple and quick. No need to remove the propeller to install. Installation underwater by a diver? … Yes, simple & easy.
Models #600 & above single piece units will require removal of the propeller to install.
The SHAFT SHARK requires less than 0.90 inch (23mm) of shaft clearance between the cutlass bearing and the propeller hub. Models #600 & above require 1.25~1.50 clearance. This allows for sufficient clearance with the cutlass bearing for shaft movement when maneuvering and for water-flow through the cutlass bearing.
Drag:
The SHAFT SHARK is sized to both the shaft diameter and the propeller hub diameter to ensure the lowest drag factor for the boat. Overall drag will vary depending upon the speed of the boat … the propeller hub diameter and the size of the SHAFT SHARK installed. This is why there are different model units to suit the shaft and hub combinations.
Maintenance:
With no moving parts maintenance is minimal. There are no moving parts to maintain or replace on an annual basis. The edges can be re-sharpened when necessary.
Models / Sizes
Sizes and Models available:
Model #300 ~ Available as a split unit only
For shaft diameters of … 1.00" … 1.125" … 1.25" and 25mm … 30mm.
Model #400 ~ Available as a split unit only
For shaft diameters of … 1.25" … 1.375" … 1.50" … 1.75" and 30mm … 35mm … 38mm … 40mm
Model #500 ~ Available as split & single piece units
For shaft diameters of … 1.50" … 1.75" … 2.00" ... 2.25" ... 2.50" and 38mm … 40mm … 45mm … 50mm
Model #600 ~ Available as a single piece unit and a split unit also
For shaft diameters of … 2.00" … 2.25" ... 2.50" ... 3.00" and metric sizes also
Saildrive Models ~ Available as split units only
SS 585T ... for 2-blade propellers
SS 695 ... SS696 ... for 3-blade propellers
Model #700 ~ Available as a single piece unit only
For shaft diameters of … 2.50" … 2.75" … 3.00" Metric sizes available
Model #900 ~ Available as a single piece unit only
For shaft diameters of … 3.50" … 3.75" … 4.00" … 4.50" Metric sizes available
Custom shaft diameters are available on request. There will be an additional charge of US$65.00 per unit.
To determine the correct Shaft Shark for your installation simply supply the following:
1. Shaft diameter
2. Diameter of the fwd end of your propeller hub
3. For Saildrive models please supply the make and model of the SD propeller
Recent Installations
Sabre 42 ... sailboat ... Model 400
Wooden Bass Boat ... power ... Model 400
Navigator 53 ... power ... Model 600
Nordic Tug 42 ... power ... Model 600
Jeanneau 45DS ... sailboat ... Model 400
Shaft Shark Installation
SHAFT SHARK - Installation Instructions:
The Shaft Shark should be installed with the labeled “AFT” side facing aft. It will be mounted flush up against the propeller hub on the fixed diameter of the shaft.
The split models (#300, #400 , #500 & #600), do not require the removal of the propeller prior to installation. It is kept securely in place by the clamp action of the two allen-head bolts.
Separate the two halves. Re-position them around the shaft, up against the forward edge of the propeller hub, and tighten in place with the two bolts.
The single piece model (#600 & above) will require removal of the propeller for installation.
Remove the propeller. Slide the Shaft Shark onto the shaft. Re-install the propeller. Position the Shaft Shark up against the forward edge of the propeller hub and tighten the set screws.
It is then held in place by set screws into the shaft.
Note: In each installation it is advisable to use loctite or similar on the bolts/set screws.