Borg Warner Overdrive problems

Brother Hesekiel

Brother Hesekiel

Senior Member
I have a Borg Warner R10 overdrive on my Model A. Last time out I noticed that it didn't engage, and since I'd like to take that car to the Horseless Carriage New Year's tour on Sunday, I'll need to figure this out today or will have to take the "T" instead.

It all seems to be okay. I can push the overdrive into the driveline using the mechanical push/pull lever. If the throttle is released, the car coasts, as it should. When I flip the electric switch to engage the overdrive, the red control light for the electric solenoid goes on but it doesn't engage. When in rest, the engine off, if I flip the switch, I hear the click, so the soilenoid appears to work.

I have a second solenoid that I bench checked yesterday. If I apply power to it (it only has power and gets ground from the body), the pin pushes outward about 3/4 of an inch. I haven't removed the solenoid that's currently installed, but that's on the to-do list for today.

I wonder what the possible problem could be. All I can think of is that perhaps the governor that's mounted to the right side of the overdrive is malfunctioning and doesn't allow the pin to do its job. Any thoughts?
 
the governor contacts is what grounds the solenoid windings.
They can get gummed up and not ground very well. Easy to remove and clean. That is a simple first step, since the pin does protrude when you bench test the solenoid. Remember the solenoid has 2 windings, a pull-in and hold-in. Ohm them both out. The pull in uses more amps than the hold in.

As you know be sure the OD unit does not drain its oil back into the torque tube as often happens, but this would not affect electrical stuff.

You could also try to bypass the governor by grounding out the solenoid terminal that goes to the governor, driving it, and just being sure you do not throw the dash switch until you are up to speed, which is all the governor does anyway. This would get you to the meet and back without a whole lot of tear down if you are in a hurry. Have done this many times on these units, just to buy some time
 
Check the oil level. If it is low it won't shift. Borg Warner overdrives are notorious for porting oil past the rear seal and into the banjo. Remove the fill plug from the banjo and see if a lot of oil flows out.

With a BW it is prudent to check both oil levels every 400-500 miles.

Also check that the pull cable is moving the lever to each stop. The set screw could have slipped.

Tom Endy
 
Action report: there is NO governor installed. There's a huge screw in plug where the governor would be, on top of the right side. That means the switch activating the solenoid will work at all time, whenever engaged, regardless of speed and gears.

Oil is good and looks fresh. I have checked it several times, tried to fill up, but it was always full.

When flipping the switch on the dash, I didn't really hear the solenoid work when still mounted while being underneath the car and having my hand on the solenoid while somebody else flipped the switch, several times. I took the solenoid off, but left it hooked up to the power cable, and it didn't work. I then remove the solenoid, and bench tested it on a battery, and it did work.

I'm wondering if the solenoid doesn't get enough ground from the two bolts, so now I want to make sure by giving it additional ground via a 12-gauge wire that I mount underneath one of the mounting bolts. That's it so far.

Another thing is the mechanical pull, Tom. I recently moved the T-handle to a new position, so I'll have to look into this now.
Update: lever works to both stops, in and out, as it should.
 
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It certainly does sound like a ground problem. Last i knew the coils did not get grounded via the case. There should be a third terminal on the outside of the case that would normally have a wire to the governor for ground. If there is no governor, then that terminal has to be grounded somehow, unless the solenoid has been modified internally. A voltage check as Tom suggested is never a bad idea either

On some there may only be 2 terminals, but in any case, one goes to the governor to find its ground unless the solenoid has been reworked internally or a ground provided in some other fashion

The manual appears in many places on the web. Do not pay for a copy, B-W gave up on this unit years ago and destroyed all its records pertaining to it. They were fitted to many different makes of cars. But they all worked the same. The R-11 was a heavier unit (4 planets instead of 3) for V-8 cars. Here is a link to the pdf:

http://www.packardinfo.com/xoops/html/downloads/BW_OD.pdf

there is a trouble shooting section.
 
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Brother H,
In the 55+ years I have driven my F100 I have been through the BW OD a couple of times. If all else fails, some things to check out:
Pull the cap off the solenoid, there is a set of contacts that are operated by the shaft, the shaft tends to wear through the insulator on these contacts.
If all the electrical is working properly then you could have a worn pall. The palls for an R-10E & R-10F at first sight look to be the same, NOT. They are almost a mirror image of each other. They can be installed in either unit and work for awhile, and over time the end of an incorrect pall will round off and then not stay in OD.
Good Luck,
Ed
 
Don't know if you guys are still thinking about this topic but I wonder what gives with my BW OD. There is no electrical solenoid. Just a bellcrank actuated by a cable to a lever on the floor. Separate from the push pull cable that engages the OD. Anyone know what's up with that? Thanks, Johann
 
JRHASZARD said:
Don't know if you guys are still thinking about this topic but I wonder what gives with my BW OD. There is no electrical solenoid. Just a bellcrank actuated by a cable to a lever on the floor. Separate from the push pull cable that engages the OD. Anyone know what's up with that? Thanks, Johann
Click to expand...

Someone did a conversion from electrical to mechanical pull-in. Either way it works fine. Learn how to PROPERLY use the overdrive, as there are special instructions and if they aren't followed, the O/D can be damaged.

I know on the factory overdrive on my Studebaker you don't want to pull the overdrive lever out unless the car is out of overdrive and the engine is pulling.
 
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