Jump to content

Overdrive Interlock Plunger


abelincoln
 Share

Recommended Posts

Decided to gather all the transmission parts for the 48 overdrive, and was doing pretty good until I got to the little bullet shaped plunger. I think its supposed to keep the OD from engaging in reverse, not that you could rev the engine to 22 MPH in reverse.

Question is, Where do you put it? The later model BW OD trans don't use it.

Thanks

Abe

post-43470-143142614839_thumb.jpg

Link to comment
Share on other sites

Abe, The interlock plunger slides into a bore between the slot for the pawl and the bore for the shift rail. The plunger will then contact the "V" slot on the pawl. The pawl needs to be rotated from what you have in the pic. What happens is when the shift rail is in the "lock out" position (manual lockout or reverse) the plunger is forced down into the "V" and will not allow the solenoid to engage the pawl for overdrive. When the shift rail is in the Overdrive (control knob in) position the plunger will then be pushed up as the solenoid engaged the pawl for overdrive operation.

Link to comment
Share on other sites

Dee:

You are right as usual. I discovered the passage in the OD adapter housing, you have to insert the plunger from the shift rail area with the shift rail assembly not installed. The short shaft of the shift rail assembly has a small diameter section where the plunger resides, and then moves the plunger as the shift rail is moved toward the rear lock out position and the plunger makes contact with the larger diameter section of the rail shaft.

Pretty cleaver of those Borg Warner engineers. I have diagrams for the later model transmissions that lack this feature. Don't know what I would do without the help of folks on this forum.

Thanks

Abe

Link to comment
Share on other sites

  • 2 months later...

Dave, while the "guts" of the 3 speed transmission are the same for either standard or Overdrive, the transmission case is different at the rear to accommodate the adaptor plate for the OD unit. The side cover for the transmission may also be different to accommodate the "shift rail" for the OD unit. You'll need to get a complete transmission with OD even if you swap transmission innards. The OD adds 13" to the length so a shorted drive shaft and torque tube are needed from a OD equipped car. I believe the cross member on the '41 will allow the use of the rear engine mount designed for the OD.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...