Re: R9 Overdrive

Posted by HH56 On 2012/8/8 12:29:15

The two contacts are insulated from one another. The little round button at the end of the top contact leaf pressing against the lower contact leaf is a piece of phenolic. It is shown in the contact pictured here

The contacts sound as if they are correct. 7 or the lower contact leaf is the lamp and that is grounded by virtue of the solenoid plunger end to keep the lamp on until the solenoid is fully engaged. Once almost fully engaged, plunger is in far enough that the contact end no longer touches and makes contact with plunger. Contact then opens to extinguish the lamp. You would read a short to ground until the plunger is somewhere past half to two thirds out when it opens.

The top contact leaf (6) is part of the ign cutout circuit. It is open until the solenoid is almost all the way energized. Once it passes a point then contact is grounded via the small button on the plate. That sets up the start of the ign cutout circuit. The entire circuit is still not complete because of an open set of relay contacts so engine keeps running normally until kickdown action is made. On the meter, that contact will be open or just the reverse of 7.