[Mgs] 80 B Timing question

[Steve Shoyer]

Gene:

I think it's a 4th gear switch, not connected to the OD.  You could try
seeing if you can blow air through the switch with the car out of gear (you
should not be able to do it), then put the car into 4th gear and try again
(you should be able to do it).  Electrically, it should be similar to the
reverse light (just a different gear), but that won't test the operation of
the switch.

FWIW, mine has been gone for years, with the vacuum advance connected all
the time - I think it was added to help with emissions.

--Steve (1980 MGB)

-----Original Message-----
... Now I just have to figure out how to test the OD vacuum advance switch.