Johnson Service Bulletin #627 (1958) - Synchronizing Spark and Gas, V-50

March 17, 1958. Factory procedure for synchronizing the carburetor throttle with magneto spark timing on the Johnson V-50 series. Includes original photographs identifying timing marks and the carburetor cam adjusting screw. See also Service Bulletin #607, covering magneto belt replacement and timing.

Johnson Service Bulletin letterhead
March 17, 1958   MODEL V-50 SeriesSERVICE BULLETIN #627
REFERENCE: Service Bulletin #607 - Replacing Magneto Belt & "Timing" Magneto
TO SYNCHRONIZE SPARK AND GAS - MODEL V-50
Figure 1, V-50 flywheel and magneto timing marks at positions A and B
Figure 1
Figure 2, V-50 carburetor cam adjusting screw and link to spark control
Figure 2

Like all models of Johnson Motors with synchronized control (spark and gas), provisions have been made on the V-50 model to properly synchronize the carburetor throttle with respect to spark timing.

To synchronize "spark & gas", proceed as follows:

  1. Turn fly wheel over until timing marks on the manual starter housing, flywheel and crank case fall in line - position "A" Fig. 1.
  2. Turn speed control grip or lever until timing marks on the magneto pulley, breaker point housing and magneto support bracket align. Position "B" Fig. 1.
  3. Note synchronizing mark on the carburetor control cam and adjusting screw - Fig. 2.
  4. With magneto set as described in paragraphs 1 and 2 above - loosen cam adjusting screw - Figure 2. Move cam to position where the synchronizing mark aligns with center of the cam follower (roller) as shown. Tighten adjusting screw to secure in this position.
Very truly yours,
JOHNSON MOTORS
Arvid Olson
Arvid Olson
Manager - Service Promotion
vlSuperior Service Spells Satisfaction

Related factory bulletin

Service Bulletin #607 describes replacing the magneto driving belt and timing the magneto, the procedure referenced by SB-627.

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