When To Check Timing - CEN-TECH 40963 Set Up And Operating Instructions Manual

Engine manufacturers use two terms
when describing timing, "advanced" and
"retarded". Timing is advanced when the
spark occurs before the piston reaches
the top of a cylinder. Timing is retarded
when the spark occurs after the piston
has started down in the cylinder. Timing
is changed by adjusting the ignition
distributor.
To set timing, the engine
manufacturer provides "timing marks"
on engine's vibration damper. Read
the vehicle's manual or contact the
manufacturer for the location of timing
marks on the engine. Also, refer to the
vehicle service manual or contact the
manufacturer for the timing specifications
for the particular engine.

When to check timing

The instant that the spark plug
fires is determined by the opening of the
distributor ignition breaker points and will
change any time the point gap or dwell
angle is changed. Normal wear on the
breaker point rubbing block will change the
dwell and effect the timing.
Most late model vehicles are
equipped with "breakerless electronic
ignition systems" and will not allow
a change in timing, because there are
no breaker points. The Timing Light
can still be used to note changes in the
timing caused by problems in the ignition
system or for resetting the timing when
components are changed (i.e. removed
and/or replaced).
SKU 40963 For technical questions, please call 1-800-444-3353. Page 7