Quoted from pinball4ever:
This is a good thought. If you look at the pic on IPDB, look at how dirty this unit is. On some older EM's, you have to sit and play with these units for hours to get them to behave like they did when the game is new (meaning moving freely around in circles when triggering it). Also, make sure to clean the wiper contact plate with a green scotch brite pad or equivalent. If these brass contact points are really dirty (on any of these types of assemblies), the game will never work correctly.
You could try manually ejecting the ball into the shooter lane once everything resets. Maybe the coil's burned out? Also, sometimes there is a switch that's triggered once the ball is shot from the outhole to the shooter lane (although I have no idea if there is with this game).
I looked at all the leaf wiper contacts inside the backbox on today's repair session. I physically removed each of the scoring reels and inspected the leaf switches and cleaned up the contacts (just to make sure I hadn't missed anything). I found one switch actuator was mis-aligned and not located in the correct position. The "ones" and "tens" scoring reels have wiper contacts as well as the triple leaf switches. I removed the reels from the spindles and cleaned the contacts, assembled and re-installed.
You may have seen on the inside of the coin door there were two cut wires from the slam tilt switch, I had to twist them together.
On power up, everything appeared as per previous attempts.
Added credits direct at the credit wheel.
Pushed the start button, hey presto the scoring reels reset to zero and a ball ejected into the shooter lane.
Everything appears to be working on the playfield and a game can now be played. I know I have to do more work to the ball counter assembly as at the moment it appears to be playing an endless game.
I have added a couple more pics of the reel assemblies, manly to show the triple leaf and wiper switch setups.
Many thanks for the hints, tips and information!