May 10, 1962
Bulletin No. SB-898
Carburetors
SUBJECT: Screw drivers for replacement of fixed jets.
Complaints have been received to the effect that orifice plugs and threads
are damaged in removing and replacing the plugs,or jets,on the fixed jet
carburetors. This can be expected to occur each time a screw driver is used
which has a blade wider than the slot in the jet, or one which has a flare
in the blade.
This problem can be remedied by one of the two following methods:
1. (a) Using a round shank screw driver, any length from 6" to 10",
which has a shank diameter of 1/8" minimum, 3/16" maximum...
(b) Grind width of the blade's flare to above dimensions to obtain
a straight blade.
(c) Bevel sharp edges formed by grinding to further reduce chance
of damaging threads.
2. Purchase commercially a screw driver designed for occasional
carburetor work. These have a round, straight shank (no flare
of the blade), and vary in length to provide for any required
reach. Since changing carburetor jets is an old practice in
the automotive field, such screw drivers are readily available
from local automotive parts houses, tool jobbers, etc. Be
certain the shank's dimensions fall within the specified
1/8" minimum, or 3/16" maximum.
JOHNSON MOTORS
W. W. DeWees
Service Department
WWD:eb
NOTE: Post on your RD (40 h.p.), RK & V-75 indexes.