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Investigations have revealed that excessive propeller cavitation is occurring as a result of certain boat builders constructing boats with transoms higher than that prescribed by O.B.C.

As a reminder, there are only two transom heights: one is 15" for the standard shaft engines and the other is 20" for the long shaft models. We have found quite a number of boats with transoms varying from 3/4" to 1 3/4" too high and it is these boats that have caused Propeller cavitation.

It is strongly recommended that you study page 5 of the 1959 O.B.C. Standards Manual which you have just recently received and make certain that all of your boats are in accordance with these recommended practices. Such items as engine well dimensions, cutout dimensions, transom angle, etc., should be studied thoroughly so that the maximum of safe and efficient performance may be obtained with every rig that you sell.

Also, you should measure your boats yourselves to make certain that all recommendations are followed. We have found some boats with dimensions that do not correspond to their factory specification sheets.

In addition, it is suggested that every dealer exert as much pressure as possible on his boat suppliers so that all boats will be built to 0.B.C. recommended specifications. Only in this manner may we obtain the safety and efficiency which we in the marine industry owe our customers.