You can also disconnect the wire that comes from the switch at the terminal board on the tin of the engine at the 7:30 position when you look at the flywheel.
I am not sure that is correct, you cannot disconnect that single one that comes up the front of the flywheel tin, that is the wire that feeds the SSI module at least it is on my 16's. Check that wire though as if it gets chaffed off, it will ground out and prevent spark. Should have I think 137ohms resistance or you can hold between your fingers and turn flywheel over by hand should feel some tingle.
To eliminate the switch circuit to check it, disconnect the 3 wire plug that comes from the rear of the flywheel going up to the regulator. The 2 outside wires are for the reg, the center wire is the kill wire going to the switch. You can disconnect it for a bit with no issues, the battery is only needed to start the motor, once running the stator creates it's own power to run. If still no spark, then it's not a switch issue.
I had 2 modules go out intermittent once motor got hot after 20-30 mins of running, I went through 2 modules within 1 month . They would be fine, then motor would die. After 10 mins of cool down it would srtart back up until module finally bit the dust.
I have a custom battery coil conversion on my OH160, but we removed the flywheel pins, glued in a magnet and use a pickup switch like on Kohler puller motors.
If you want a direct easy cheesy replacement, look at Dale Colvert's Overnight solutions ignition. It runs around $150 and works just like the factory module.
You can also convert over to a battery coil system, check out Ed SToller's www.enginesandmagnets.com site, he sells a pickup, tells you how to do it or he has a friend who sells a complete kit with all proper components.
I have another 16 I will be doing a conversion on, I am going with Dale's system this time around so I don't have to worry about having a good battery or charging system in case something goes wrong.
There is no way I would pay the highway robbery people are wanting for the 40 yr old used parts on evilbay when you can buy new electronics that can be replaced easily much cheaper.
Mine are all on the 16 Hp on Sears, but should be basically the same. I've learned way more than I ever wanted about these stupid things over the last year.
Edited by TAHOE, May 02, 2013 - 08:22 PM.