Getting over my overdrive ...

[John Snyder]

Byron,

I agree w/ Doug.  The "engage" circuit of the solenoid pulls a lot of amps, 
but only for a second .  Once engaged, the O'D should go into the "hold" 
position.
If that does not happen, the Lucas smoke is released.  The smoke is a 
patented Lucas product, and is no longer available, therefore you must start 
at ground zero.  You can check the engage/hold w/ an ammeter.  You may want 
to check the travel of the small arm connected to the O'D shaft on the right 
side of the unit.

Re the rubber button, I go to the local parts house/hardware store and buy a 
button that is for the glove box door of an American car.  Works great.

John Snyder




> Hi Byron,
> I have had intermittent disengagements and unpredictable failures to 
> engage for over a year with my BN 2.  Every time I tried to diagnose the 
> problem the solenoid would perform as it should.  However the last time I 
> had the tunnel off and went through the drill several times, the solenoid 
> finally failed to actuate.  I put my hand on the solenoid housing and it 
> was very warm.  A few minutes later it cooled down and worked again.  I am 
> assuming I have had an intermittent internal short inside the solenoid.  I 
> put on a new solenoid (from Moss) before going to the Rendezvous.  It 
> worked every time.
>
> You should put an ammeter in the circuit to ensure that the steady state 
> current is dropping from the pull-in current of about 12 amps to the 
> hold-in current of 1 to 2 amps.  The pull-in current will burn out the 
> solenoid if the limit switch inside the solenoid fails to work or engage.
>
> The lack of a rubber bumper or other stop mechanism can allow the solenoid 
> plunger to drop below the level where the magnetic field will pull the 
> plunger into position.  I assume when this happens the solenoid will 
> continue to pull 12 amps while the overdrive switch is closed.  I made my 
> own bumper from a rubber insert similar to those at the bottom trunk lid 
> lip.  Some guys tap the stop land on the housing a use a small screw that 
> gives them the ability to adjust the level of the stop.