Overdrive Solenoid

[Stu 1986]

Hello Chaps
The gearbox fitted to the Vitesse engine in my Herald is fitted with a D Type overdrive. I was looking at the solenoid which looks as though it hasn't been disturbed for some time, and I was wondering how I would go about testing the solenoid works? I can only see one wire coming out of it, so am I correct in assuming that the unit is earthed to the gearbox?

Any tips on testing it would be appreciated. I hope that it doesn't need replacing, it looks like a pig to remove.

Stu.

[Darren Sharp]

Hi Stu you are correct, it earths through the box. test is quite easy if the car is live (ie battery fitted). turn on the ignition and listen to the solenoid whilst flicking the switch. or if not take a12v live source to the one wire and earth to the box. same thing you should hear it operating .
Darren

[Pete Lewis]

removing a d type solenoid is difficult due to access to the lower screw.

you can test this , with simple tools and a cheap multimeter.
suggest you remove the square plate in front of it,  when the solenoid is 'on' it pulls a lever under this cover, the lever has a 1/8" hole in it , use a drill shank as a tool and it should fit thro the hole and align with a similar hole in the case behind the lever.

adjustable by the nut on the sol pull rod.

there are 2 coils in the solenoid and a built in  sealed switch,
  coil 1 pulls the armature in only a few mm and takes a current of around 10 amps,  as the armature hits the end of its travel ( and the lever hole is aligned ) it presses a sealed switch in the rear end of the solenoid and this cuts the pull in coil and now feeds a hold in coil , this coil takes only 0.5 amps and is what should be in operation whilst driving
the 10  amp  initial  pull in only lasts for a fraction of a second but because of the current load requires a relay feed ,  

if that helps

Pete

[dave mc]

So glad you asked that question Stu, as I have been thinking about testing mine whilst out of the car.

[Stu 1986]

Thanks for the replies so far chaps, I'll test it at me next opportunity. I really wish I had tested this when the engine was out of the car, but that was 7 years ago and I knew nothing of it's existence. I really hope it is working, I would hate to have to change it at this stage of the build, it looks pure awkward to do. :/

S.

[Pete Lewis]

its said you can get the lower screw undone if you jack the gearbox tail up fairly high,  like disconnect the mounting rubbers and lift till clear, !!!!
   if refitting use socket cap screws , then its do able with a flexi drive and hex bit

Pete