I have a manual on the Tecumseh ohv 130, but it seems that the problem is not to do with this, its on the unit itself, reading you lost post re (*78) check list, the owner should be able to work it out, I can't add anymore to what you say in that post, we know its intermittent, it seem's that its not the solenoid, so that leave's key switch and I believe that is working fine..! if checks are now made to all wiring, all connections, and all safety switch(s) like you say, working one's way from key switch to solenoid, one may (will) find a switch(s) that will need a good clean or to be replaced.