Airboat Propeller Installation Instructions

Congratulations on the purchase of youra new Whirl Wind airboat propeller – the very best there is! Your new Whirl Wind not only offers excellent performance nd durability, but easy assembly and blade pitch adjustment as well.

To ensure years of trouble free service – READ and FOLLOW ALL DIRECTIONS. Failure to do so may lead to propeller failure.

• 5/8" socket
• 1/2" socket
• ratchet, and
• torque wrench

Step 1

Carefully unpack your propeller from the factory box and take inventory of parts. Verify parts and hardware supplied, agree with packing list.

• 1 – Hub (front & back)
• 1 – Spacer
• 6 – 7/16" bolts & washers
• 2 – 7/16” bolts & washers per blade
• X - Blades

Step 2

Place the propshaft side of the hub half on a clean flat table.

Place the flat spacer in the center on inside hub half.

Carefully place blade shanks into the hub.

Step 3

Place the second half of the hub over the other half of the hub, spacer and blade shanks. Gently lift the blade tips and seat the hub halves. At this point, install the 7/16” bolts (use an anti-seize compound on threads) into the hub. Take care not to cross-thread these bolts into the hub. Repeat this for all blades. Tighten the 7/16” bolts so the prop blades are firmly held in hub, but so that the blades can still be smoothly rotated in the hub.

NOTE: Do NOT force or hammer any propeller parts together.

Step 4
Install the Propeller on the Airboat

Make sure your propshaft is clean and free of rust and corrosion. Mate propeller to propshaft and install _” bolts. Tighten bolts symmetrically and make sure propeller is securely pulled up to propshaft – no gaps allowed. Next, torque 7/16” blade shank bolts to 45 ft-lbs and _” propshaft bolts to 55 ft-lbs.

Blade Track: Check the blade track to ensure the blades are within 0.100 inch of each other and that the blades are held firmly in the hub. Ensure hub has been installed flat against mounting flange, and ensure that each blade is well seated in the hub (not misaligned or crooked).

Blade Movement: Any blade movement in the hub is unacceptable.

Step 5
Initial Pitch Setting

To set the initial pitch, line-up the mold parting line of each blade on the leading edge to degree marks on hub. The propeller has been designed to operate from 10 degrees to 25 degrees for optimum performance.

Initial Pitch Setting: Start with a pitch setting at about 20 degrees (refer to Step 7 – Maximum RPM Setting).

Note: For 70” and 72” SP blades, there is an optional reference mark located _” back from mold line for use on higher horsepower engines.

Step 6
Inital Engine Run-Up

Important Note: Before starting your engine and new propeller for the first time, ensure the propeller blades clear all engine parts (suggested minimum clearance of at least 2”). Repeat this step each time you change the pitch setting of your propeller.

Run the engine up to 2000 propeller RPM. Shut down the engine and inspect the overall condition of blades, leading edge and hub. Firmly grab each blade tip and apply a forward and aft force in ensure each blade is tight in the hub. Do not operate propeller if blades have any movement in hub. Check for proper torque on all bolts ( 7/16” bolts to 40 ft-lbs -- 1/2" bolts to 55 ft-lbs ).

Check bolt torque and perform visual inspection as described in “Care and Maintenance” after every 20 to 25 hours of operation. Enjoy your new propeller and have fun!

Step 7
Maximum RPM Setting

You may run the engine up to max. engine RPM, but DO NOT EXCEED MAX. PROPELLER RPM!

Max Prop RPM

• Diameters 70” to 80” = 3000 RPM max
• Diameters 82” to 84” = 2700 RPM max

To find the pitch setting for maximum RPM, start with a blade pitch setting of 15 deg. (The degree marks on the hub range from 10 deg to 25 deg.)

• if the engine RPM is low - decrease the blade pitch to increase RPM;
• if the engine RPM is too high – increase the blade pitch to decrease RPM.

For Maximum push performance the Whirl Wind Propeller is designed to turn 2500-2900 RPM static. This propeller RPM range will deliver maximum thrust. You may not want or need to turn your engine this fast if you are interested in reducing noise or increasing fuel economy.

Care and Maintenance

Proper care and maintenance of your Whirl Wind propeller will ensure a long life with many hours of trouble free operation.
A complete inspection of your propeller should be performed periodically, at least after every 25 hours of operation.

Blades

• Wash & Clean all blades with a mild detergent
• Inspect overall condition of blades, looking for chips, cracks, and any leading edge damage. If the leading edge is damaged, this can be repaired by returning to Whirl Wind with the full set of blades. If damage is neglected, it may worsen, making repair impossible.

Hub

• Wash & clean hub with a mild detergent
• Inspect overall condition of hub. Inspect interior and exterior thoroughly for any signs of hair line cracking. If any cracks are detected, contact Whirl Wind for assessment

Bolts

• Check bolt torque on all bolts
  • 7/16” bolts to 40 ft-lbs
  • 1/2" bolts to 55 ft-lbs

Note: Every Whirl Wind propeller blade is manufactured using a state-of-the-art production process that yields a smooth surface finish on each blade. There may be slight marks on the surface, such as small bubbles and/or pinholes – these marks are common to this type of advanced manufacturing process and do not affect the structural integrity of the blade.