It's an old and familiar story - as old or older than boating. The progressive build-up of marine growth simply roughens the surfaces moving thru the water thereby presenting objectionable resistance to reduce the useful effectiveness of the power applied to drive the unit - barnacles, etc., in salt water regions otherwise greenish moss or algae in both salt and fresh water. The obvious recourse then is either to remove, prevent or delay as much as possible its forming at all.

Anti-fouling paints are available for this purpose. The illustration here shown reveals the result of a ninety day submersion test in salt water and speaks for itself. The gearcase to the left was untreated when submerged. The gearcase to right was sprayed with Pettit Alumacide white.

All too often marine growth, hull and gearcase fouling are ignored or overlooked when seeking the maximum in performance. It's not uncommon to encounter speed drops of from 3 to 7 or 8 miles per hour for no apparent reason except various states of marine growth fouling.

You've got to keep your bottom (boat that is) and gearcase clean - free of marine growth for top performance.

JOHNSON MOTORSJack Penland
Service Promotion Manager