These installation notes apply only to the Martec Mark III Eliptec folding propeller series. Please Note: Do not mix parts from different propellers



(2) - Blades
(1) - Hub
(1) - Monel Pivot Pin
(1) - Key
(4) - Monel Cotter Pins
(1) - Nut


TOOLS NEEDED Wheel-puller (to remove fixed prop or hub from folding prop)
Soft rubber mallet (to tap hub if necessary)
File (for key, if slightly oversize)
Pipe Wrench (to hold main gear)
Socket wrench and extension: 3/8" for shafts 3/4" and 7/8" diameter & 1/2" for shafts 1" or larger

Optional Equipment - Drill and 1/8" drill bit


Assemble hub, key and nut on shaft. Keystock may be slightly oversized.

If necessary, file the top and bottom to insure proper fit.

Thread and tighten cylindrical nut with socket wrench ratchet and extension. Line up cotter pin holes in hub and nut, as you reach full tightness.

Do not loosen nut if opposite holes are not in-line. Instead, enlarge existing holes or drill another one with a 1/8" drill bit, using hole in hub as a guide.

Install (2) Monel cotter pins thru holes in hub; one from each side of the hub. Cut the cotters to fit and spread inside the nut.

Carefully line up pivot pin holes in hub and blades.
Important note: One blade and one ear of the hub clevis are marked "I" and should be assembled with both marks on the same side to insure proper balance.

Install Monel pivot pin, and lock it in place with the remaining (2) Monel cotter pins.

(Please note this is an option only - not a mandatory part of the installation)

Apply a small amount of medium grease (marine/trailer bearing grease) on the pivot pin and on the blade flats (where the blades make contact with the hub) at the time of installation. 

Important to remember - Always mark your shaft from inside the boat, with the pivot pin in the vertical position  (make sure you do this on both sides of the shaft)

Engage only at idling RPMs. Damage may result if gear is engaged at much over 600 propeller rpm.
Simply engage reverse and then increase throttle as much as required.

Manually rotate the shaft to the best sailing position, where the previously marked pivot pin is vertical.



Inspect all cotters at each haulout. Only replace with Monel cotter pins!

We recommend that Martec refurbish your propeller within approx. 5-10 years. The cost is nominal and it will add years to your propeller's lifetime. See our refurbishing page for a cost schedule for this service.

We further recommend the use of Martec's streamlined zinc in conjunction with any low-drag propeller to minimize drag and turbulence.
Martec zincs, Monel cotters, etc... can be purchased directly from Martec Eng. Corp.
Return to the Eliptec Mark III main page
Need to refurbish an existing Martec prop?
Get more information on Eliptec props
Check prices and availability
Return to our main page