Re: 1940 overdrive

Posted by HH56 On 2008/6/11 22:26:32

3 & ground is the hold coil and will not pull in the solenoid by itself-- just spark--but if you pull the stem out completely then it will stay out if working properly.

4 & ground will energize things and extend plunger but then should drop right back out when solenoid fully extended because a set of contacts inside are supposed to open when stem fully out.

At any rate, reading the description of operation, checking schematics the light should go out when the solenoid is fully extended and the pawl is properly engaged since a contact (terminal 7) in solenoid opens. The governor should have turned it off by dropping everything out below 22 or whatever speed it is set for. Are you sure that is working properly.

One thing I am curious about. Are the two solenoids identical in the length & travel of stem? Reason I ask is there are several part numbers for solenoids. Not sure when the R9 started, but there is a part for 17th series, one for 18 & 19th, one for post war R9s, and then the R11s. All R9 schematics are identical so what would be the difference that needs different numbers.