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Greetings from the Last Frontier,
I am having two problems that I think are overdrive (R9) related and would appreciate comment. For the most part,
the OD works as it should - engages and will kick down properly, however,

1. In second gear, after the OD light comes on, and I begin to approach the shift point to third (approx 25-30 mph), I experience a miss - as if the timing is off. Once I shift to third and OD kicks in, she smooths out. This will not happen if the OD is locked out. With OD locked out, 2nd winds out to 35-40 mph and I can maintain that range of speed smoothly with no miss or hesitation.

2. While OD is available (not locked out) and after reaching OD speed in second gear,(OD light comes on) if I let up on the gas to decelerate, occasionally I will lose ignition - engine just dies. She will restart if I depress the clutch and release and give some gas, which I suppose is just like a push start. I have never had this problem when I continue to shift up to third and engage the OD. This only happens while I am in second gear.

The common thread seems to be that both of these problems happen during the OD "ready to engage" mode. My studying tells me to first check for wiring shorts and connections to the solenoid, etc. Am I on the right track? Is it possible that the solenoid itself is malfunctioning? Any other likely suspects? To my knowledge the OD and transmission have never heen apart, but they have been rewired. Thanks in advance for comments/suggestions.

Mark

I'll let the experts walk you through the detailed troubleshooting, but as a first check, it sounds to me like the governor may be suspect in some manner, so with your first wiring review, be sure to check wiring there too...

There are 3 sets of contacts in series preventing the ign circuit being active except for the brief instant it's needed -- one in the solenoid and two in the relay box. If one set is hanging or out of adjustment, there could be enough overlap to cause an issue.

With no OD selected or locked out, 2 sets should be open preventing any problem. Wiring would be the only way ign would be shorted.

When at speed and ready for OD, ground from governor and thru interlock switches goes to the main relay & closes a large set of contacts to power the solenoid. As that relay main set closes it also opens a smaller set in the ign circuit. Simultaneously because the solenoid has power, the other relay closes it's set in ign circuit. When the solenoid is powered and in the process of moving pawl into mesh, at about the 2/3 or so point of plunger travel it's set closes. All stays in that condition until kickdown is made -- 2 sets closed, one open.

When kickdown is made, immediately the main power relay drops out closing it's small set and ign circuit is complete. Engine misses, and with power cut and torque low, the solenoid plunger releases. The closed solenoid points will open somewhere toward the last 1/2 of travel and the second relay set will open after a small delay to ensure the circuit is open in case the plunger is mechanically slowed for some reason. That entire operation shouldn't take more than a few milliseconds or as the book says a "few" ignition pulses.

As far as wiring, the wires from solenoid 6 to relay 6 and relay 2 to the coil are the ones to check. If the solenoid hasn't been opened, it might be a good idea to check and dress those contacts and make sure the phenolic insulator button separating the light and ign contacts is in good shape. The relay box could also be opened to verify the condition of those contacts as well.

Thank you Howard, extremely helpful.
Mark