Packard Forum Index » Pre-War (1899-1942)

Packard Don wrote:
If you’re not using the overdrive, nothing will happen but why do that? Unless you’re rewiring, maybe just leaving them alone is better

Ross wrote:
If you leave them disconnected for now the transmission will act as a normal three speed and the overdrive will not operate. You will need to move that one lever on the passenger side forward to prevent the trans from freewheeling. Once upon a time there was a knob under the dash for doing that but who knows if that is still there.


Looking at all the mung I can see why you say they put lipstick on a pig.

Later on when other issues are under control you'll want the overdrive to work as it makes the car freeway capable.

1941Packard wrote:.....Does anyone know where to drain/fill the transmission? I assume........

HH56 wrote:
Here is an easier to follow diagram for the overdrive. 41 uses the R9 version which is a bit more complex electrically than the later R11 overdrive. The R11 solenoid can and has been energized manually with a switch because its coils are wired differently but don't know if anyone has tried it with the R9.

In order to bring the R9 solenoid in without the relay box, both terminal 3 and 4 must be jumped together and powered at the same time. 3 is the hold coil but that coil is not strong enough to move the plunger against the spring by itself. 4 is the pull in coil and it does the work of moving the plunger but is a coil that pulls a lot of current and gets hot so gets disconnected when the plunger is fully extended. Without the hold coil also energized at the same time as the pull in coil the plunger will just repeatedly pull in and almost instantly drop out so in effect the solenoid "machine guns".

The power to terminal 3 goes thru a relay coil which increases resistance in the circuit and puts the hold coil the solenoid in a series arrangement. Whether the hold coil is able to be powered constantly at 6v without overheating because the second relay coil is not in the circuit is unknown.

There are some other functions such as the ign cutout and the kickdown that may not be able to be duplicated well without the relay. Until someone tries, no idea now much an issue not having those functions will be.

HH56 wrote:
No. The R11 plunger length that extends into the overdrive mechanism and locks into the pawl is a different length. R9 extended is about 2 1/4" and R11 extended is about 1". R9 solenoids and relay boxes are unique to that unit. R9 relays are still out there but are getting expensive. .

Resistors do not work well with solenoids and overdrives in general. Trying to run a 6v overdrive at 12v using a dropping resistor is almost a guaranteed way to burn something out. The solenoid pulls a heavy current when moving but considerably less when just holding in an extended position. The value and wattage of a resistor would need to be different in each situation to get a proper voltage drop.