Posted by Chris on December 05, 1998 at 20:21:49:
In Reply to: quirky ignition system on my '67 posted by Susan on December 05, 1998 at 16:16:29:
Susan-
I don't know what kind of truck you've got, but here's some
general info:
The starter's gear must only be engaged to the flywheel's teeth
during turn-over. To achieve this, the gear on the end of the
starter thrusts out on its shaft to mesh with the flywheel, and
returns when you release the key.
A typical sequence goes like this:
the key is turned to start. the starter draws too much juice to
have all that electricity running through a tiny switch in the cab, and
you don't want the starter turning until it's meshed with the flywheel, so
the key switch actuates the part of the starter (solenoid) that throws
the starter's gear out to meet the flywheel (or alternately the gear itself
rides on a spiral-cut shaft (bendix) that throws out centrifugally after the
has started turning. The solenoid is also set up so that at the end of its travel, it acts as a switch and completes the circuit
fires up the starter motor. When you turn loose of the key, the starter is shut off and the starter
gear retracts.
Hope this helps you figure things out. Sounds to me like the starter's gear isn't making it to the
flywheel before it starts turning.
-Chris