[6pack] starters, ring gears, etc

[oliver]

Over a year ago I had trouble with the starter engaging.  If I turned the
engine manually about 90 degrees it would engage better.  Then eventually that
stopped working.  So we removed the tranny and the flywheel, discovering that
the ring gear had started to move away from its location, preventing the
starter from engaging.



I had purchased a new ring gear since I wasn't sure what the problem was.  I
took it to be installed on the flywheel, and the machine shop told me the old
ring gear was in backwards.  I attributed this to the supplier of the
lightened flywheel, wrote it off to experience, and had them install the ring
gear "correctly."



About a year later the starter motor quit engaging the ring gear (again).
Pulling the starter motor revealed that the top quarter of the gear was
completely chewed off.  This is a high torque starter.  Further investigation
and discussion revealed some interesting information.



The orientation of the starter on TR motors is from the engine compartment
with the active part facing the rear/passenger compartment of the car.  The
ring gear has beveled edges which should face into the gear of the starter
motor.



>From what I understand, some starter motors pull the gear into the ring gear
from the back of the car; all high torque starters push the gear from the
front into the ring gear.  From what I can tell, and this is approximate, the
TR2/3 starters, also called bullnose, pulled the gear back into the ring gear.
TR3a, TR4, TR250, and early TR6 up until late 1972 TR6 pushed the gear
forward.  Then it reverted to the early style (pulling the gear back into the
ring gear) for the rest of TR6 production.



If this isn't correct, please feel free to chime in.  I think I now understand
this issue, but if I'm missing something I'd really like to know that.  This
is an issue which I would love to hear more about, and if you are considering
a high torque starter something that you need to understand.  What I have yet
to understand is how/why my ring gear got pushed forward and out of reach. Is
the answer is to have the ring gear pinned so that this does not happen?