[Mgs] LH overdrive trivia

[Ed Woods]

List,

I've got an MGB with an LH overdrive that won't engage. No pressure on the 
gauge. Solenoid seems weak. Grounding is intermittent. Working under the car 
with power to the solenoid, I find that, with the solenoid cover removed, 
simply moving the solenoid housing will cause the plunger to be pulled in or 
dropped out. On the bench, the solenoid moves the plunger with very little 
force, hardly enough to pull it against its own weight. I've already tried a 
second solenoid with the same results. Of course I'm comparing it with an 
'A' type solenoid with which I'm more familiar. An 'A' type really snaps 
into place!

So what kind of "pull" force should I expect? What current should the 
solenoid draw? How is the copper wafer on the bottom of the solenoid 
expected to contact earth through the oily film surrounding it? Where can I 
find this trivial data? Any ideas on how I might manually move the plunger, 
move the ball against its seat and then observe o/d pressure??

TIA,

Ed Woods