Figure 7. Cam angle test connections.
protractor setting knob so a flashing cam
lobe alines with "0" (4 - 6 - 8) mark, as
b. Check the pattern on both speed
30. Cam Lobe Test for Distributors Without
ranges from 200 to 2000 rpm. Image pat-
Automatic Spark Advance
tern should remain steady on the "0" mark.
"Dancing" or misalignment of lines at high
a. Turn the motor switch (17) to the di-
speed only, indicates bounding of points,
rection in which the distributor shaft is
poor contact, weak springs, or friction in
driven in the vehicle and with the distrib-
breaker arm bearing.
c. Turn the speed control handwheel
observe the cam pattern on the strobo-
fully clockwise, set the motor and direc-
scope. Adjust the protractor disk with the