[TR] Overdrive Woes - new question

[Randall]

> On a related issue (sort of) - is there an overdrive lockout switch that
> works opposite of normal? Specifically, normally "ON"?

I'm not aware of one, that fits the predrilled holes.

> A friend has a TR4
> withan OD but the topplate only has the reverse light switch location
> drilled out.

Of course, the proper solution is to drill and tap the other two holes; or
trade top covers for one that is already drilled and tapped.

> He would like to use that location for a switch that would
> lock out the overdirve in Reverse.

Although the damage isn't nearly as severe as reverse, operating a standard
A-type in 1st gear is also pretty hard on the unit.  Since the OD has to
handle the multiplied torque from the engine, it 'sees' much more torque in
1st gear, but the relatively low shaft speed means the pump output is very
low.  The result is very likely to be slippage under some common conditions,
like pulling away from a stop sign, which will lead to rapid clutch wear.

> Or perhaps there is a solenoid that
> would produce the desired effects?

Sure, all you need is a relay with a "normally closed" contact.  Most
general purpose automotive relays have a NC contact, for example eBay
280258230235.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280258230235

> Did we have this discussion before? I can't find it in the archives.

Beats me.  Did we?

Randall