[TR] TR2 - Rope Fan Belt and Non-stopping Generator

[Dave1massey at cs.com]

"Randall" <tr3driver at ca.rr.com> wrote:

>>  The odd thing was that the generator was still spinning.  It 
>> continued to spin until I disconnected one of the wires.  Can 
>> anyone explain why?
>
>That would indicate that the cutout relay in the control box did not open as
>it should.
>
>> It seemed like 
>> it turned into an electric motor.
>
>Exactly right.  Electrically, they are the same thing.  When the engine
>turns the generator faster than it wants to run, it generates power.  But
>with the engine not turning it, the generator would act like a motor except
>that normally, the cutout disconnects it from the battery when the output
>voltage drops below the battery voltage.
>
>> Did I somehow reverse the polarity of the generator?
>
>Possible, I guess.  Couldn't hurt to try repolarizing it, but I don't think
>it will help.  And of course it won't solve whatever is wrong with the
>control box.
>
>> Any help would be greatly appreciated.
>
>The steps in the attached booklet are reasonably straightforward, and should
>quickly lead you to the problem.  Don't forget that there may be multiple
>problems, so perform all the tests before deciding which units to replace.
>If you are lucky, it's just the control box ... but unfortunately, driving
>with the control box on the fritz may have fried the generator as well.
>
>Randall
>

The cutout relay opens up in response to large currents flowing into the generator when it comes to a stop.  Since the generator never came to a stop there was no large current.  And the lower lever of current flowing into the generator to spin it was not sufficient.  I suspect there is nothing wrong with the control box.

The same thing happened to my MG back in the 70's.  New belt and all was fine.

Dave