Yanmar MOI

YANMAR MARINE:

To: All Yanmar Marine Distributors: Ref No: FSTB 09-02

Date: Sept 2006

REGIONAL TECHNICAL BULLETIN

Subject: Propeller Selection on Yanmar Marine Sail drives.

Yanmar Marine International B.V would like to inform you as follows:

As there are more and more different propellers available from several manufacturers Yanmar Marine International

has decided that whatever brand or type of propeller is selected is not of influence on the validity of the Yanmar Marine

limited warranty for the Sail drive as long as the propeller is in accordance with the below data.

Please contact your propeller supplier in order to check if the propeller selected is manufactured in accordance with the data below.

Propeller limitation for Yanmar sail drives SD20, SD40 and SD50

                           Propeller types which are allowed to use on each Yanmar Marine SD model under specified conditions:

                           a. 2-blade, 3-blade and 4-blade propellers

                           b. Fixed-, Folding-, Feathering propellers

                           c. Propellers under a & b require rubber bushing to reduce shock torque and electrical corrosion

SD20 sail drive model:

- Max allowable shock torque: < 145Nm.

- Max allowable Moment of inertia (kgm2) in relation with static torsional spring constant ( Nm/deg) see graph

SD50 and SD40 sail drive model:

- Max allowable shock torque: < 227Nm.

- Max allowable Moment of inertia (kgm2) in relation with static torsional spring constant ( Nm/deg) see graph

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