February 16, 1966
Dealer Letter #139
Gentlemen:
From time to time we have had reports from the field that certain Coast Guard or Coast Guard Auxiliary personnel have questioned the adequacy of the fuel tank area ventilation on 1966 Johnson boats.
At the New York Motor Boat Show all models of the 1966 Johnson boats were on display and each model was personally inspected by G. H. Dickman, Commander, U. S. Coast Guard, Recreational Boating Safety Division. A form was completed after the inspection and we, as manufacturers, were advised on January 28, 1966 by letter from Captain D. W. Sinclair, Chief of the Recreational Boating Safety Division, that there were no discrepancies in regard to adequate ventilation on the Johnson Caprice, Reveler or Surfer.
The points covered in the inspection for which Captain Sinclair did not record any discrepancies at all were:
1. Cross section area of ventilation inlets and outlets insufficient for beam of vessel or net volume of compartment. a. Ducting too small b. Hull openings between cowls and ducts too small c. Cowl openings too small - screen and/or grill further restricts openings.
2. Louvers used in lieu of cowls with effective open area insufficient to be equivalent to cowls. Effective open area must be at least equal to that which is required for ducts. (Because of decreasing effectiveness of downwind vanes of louvers due to obstruction from upwind vanes total open area is not the governing factor; volume of air flow is.)
3. Intake ducting does not extend at least below carburetor level.
4. Exhaust ducting does not extend to lower portion of bilge.
5. No intake cowls or ducting.
We strongly recommend that you keep this letter handy to show to any local Coast Guard or Coast Guard Auxiliary personnel whose personal interpretation of the ventilation requirements may differ from that of the Chief of the Coast Guard Recreational Boating Safety Division.
Very truly yours,
LWE:eb