Mounting on all SAILDRIVES over an industry standard SAE  16/32  17 tooth spline on 28 - 28.15 mm ø shaft.

First ensure that both internal and external splines are scrupulously clean.

While every effort is made to remove any burrs from the castings on the internal splines  these can cause jamming when mounting and may need a wipe with a file as manufacturers spline specifications can differ by up to 0.15 or 0.006".   The unit has been prefitted over a manufacturers spline and should slide easily onto the spline on the any model of Saildrive.

Check the ~10 mm thick collar with seal shield is on the shaft. (Yanmar # 196420-09250 Volvo #  851984 )

Remember if you are fitting to units that previously had cutters installed - then these would have required the removal of the guard collars designed to keep monofilament line off the bearings and accept the forward thrust of the propeller.

Check the GF PP nose cone is not binding on the zinc. Some units such as Lombardini come with collars and washers which must be mounted. All Saildrives require that the distance from the end of the spline to the face taking the thrust is exactly 3.000”  or 76.20 mm.  

CAUTION: Larger 3rd party zincs may bind on the nose cone and would need to be filed down

All Saildrive propellers then have bosses which are ~ 3.125” or 80.00 mm long to ensure they pull up tight on the thrust face before the M16 x 2  (M20 x 2 for Yanmar SD40, SD50 & SD60 Saildrives) nut starts to bind at the end of the thread.

NB: The first batch of SD60 Saildrives ex ZF were manufactured with M20 x 2.5 in error

Remove the 2 x M8 locking grub screws at the rear of the unit to expose  ~ 80 % of the thread,  Coat all thread surfaces in Loctite™.

Apply Loctite™ to the main M16 or M20 Attachment Nut thread:  ---   All are Right Handed and tighten clockwise. The grade of Loctite™ is not critical - a blue medium strength is recommended.

Tighten the main attachment nut using the socket set - minus a socket.

DO NOT overtighten the nut which attaches to any standard ½ inch socket driver.

SAILDRIVE attachment nuts should be tightened to a torque of  ~ 50 ft-lbs  or  ~ 70 Nm.

Screw the 2 x M8 lock screws @  90º location with Loctite™ on the threads into nut and tighten down securely now that the main attachment nut retaining the propeller is correctly locked in. Work back and forward to ensure set into the nut.

NB: A FAILURE TO TIGHTEN THESE TWO LOCKING SCREWS AND SECURE ALL THREADS WITH LOCTITE™ CAN LEAD TO THE LOSS OF THE ENTIRE PROPELLER UNIT OVER TIME ON A SAILDRIVE UNIT.

Saildrives post  serial # 8650  ex 2008 have an additional M8 x 40-45 failsafe Right Hand SS 316 Cap screw as used by Volvo that provides an additional level of locking security where the splined boss can never be tight on the parallel spline. The pitch differential between these two components provides the locking effect.

Apply Loctite™ to the thread and underside of the head the M8 Failsafe Cap Screw - then fit & torque inside the square drive main nut recess.  Again, a medium strength blue grade is recommeded.

This M8 Cap Screw should be tightened to  ~  5 ft-lbs or ~ 7 Nm.

We suggest a medium grade of Loctite™ to ensure subsequent ease of removal.

NB: Saildrive nuts and their locking screws should be checked and re-tightened at each haul out as Splines by their nature may fret slightly in use and could loosen the locking screws. If any movement remove and re-apply Loctite™.