February, 1966
SB-#974 Rev. 1
SUBJECT: #381649 Restrictor Plate and Gasket Assembly
ENGINES AFFECTED: All 18 and 20 h.p. (Models FD and FDE).
We are informed that the use of an outboard motor developing more
than 15 h.p. is prohibited on some bodies of water. No doubt this
has affected owners of 18 and 20 h.p. Johnson Outboard Engines in
these areas, and, as a result, dealers have requested instructions
for restricting the 18 and 20 h.p. engine to 15 h.p. (Models FD
and FDE).
Our Engineering Department has developed restrictor plates which
can be installed between the carburetor and intake manifold of FD,
FDE - 18 and 20 h.p. engines, limiting the maximum attainable power
under load of 15 h.p. This should meet with the approval of local
authorities, making it possible for an owner to operate an "ENGINE
RESTRICTED TO 15 H.P." on these waters.
The following parts in assembly
#381649 (shown in Fig. 1) are
required to make this conversion:
2 pc. #203237 Gasket
1 pc. Restrictor (18 to 15 HP)
1 pc. Restrictor (20 to 15 HP)
The installation of the proper
restrictor on an 18 or 20 h.p.
engine will in no way affect or
limit the policy governing war-
ranty to any engine still within
the warranty period - SO LONG AS
IT HAS BEEN INSTALLED BY AN AUTHO-
RIZED JOHNSON DEALER.
The restrictor plate has a tab
which protrudes above the carbure-
tor (Fig. 1 & 4) to enable quick
identification of 18 h.p. engine
restricted to 15 h.p. or 20 h.p.
engine restricted to 15 h.p.
Assembly #381649 will be provided
at no cost to any Authorized
Johnson Dealer upon his request
to the factory service department.
Be sure to send along model and
serial number of engine receiving
modification. (OVER)
