OverDrive Trans help please

Val
Val Member
I have what I believe to be a 1950 O/D trans in my 39. Not sure that it is kicking in now. What re some things to check?

Comments

  • Jon B
    Jon B Administrator
    Wiring, and terminals (make sure nothing's broken off the transmission). 

    Do you mean that, with the knob in and overdrive "enabled", it doesn't click into 4th gear when you lift your foot off the gas?

    If so, the problem could be electrical (governor switch?), or it might be in the mechanical cable that goes from the knob down to the lever on the side of the OD.  When knob pushed in all the way, is it moving the lever on the side of the OD all the way back to its limit?  Try unbolting the cable from the clamp at the arm.  Now, can you move the arm back further?  If so, then the cable must be re-positioned and the arm clamp re-tightened.  If NOT, then....that wasn't the problem, LOL!
  • Val
    Val Member
    Thanks Jon I will check all that and send you a PM on the club forum But I thought the knob had to be pulled out. HHMM maybe that is my problem??? LOL 
  • Jon B
    Jon B Administrator
    Check your instruction book.  I have the "first gen" of Hudson OD and the knob is OUT for regular 3-speed direct drive, and IN for overdrive.  The later OD's might be the opposite, I dunno.  Check it out!
  • Geoff
    Geoff Senior Contributor
    Knob has to be  all the way in for o/d to work.  Check that the lever on side of o/d is right back when  the knob is all the way in.   Otherwise, check the  governor switch, that it provides ground circuit to the relay.
  • Val
    Val Member
    Thank you Geoff, I really appreciate you guys help in this as I am new to all this and it is a mod that was done. I'll update when I get the chance to check all this. Hopefully today after work I can get to it.
  • Val
    Val Member
    Ok Guys I have checked so far the travel of the lever at the trans when the knob is in the fully extend and pushed in fully positions. It does travel to the full distance. Here is the Gov. (centrifugal Switch?) where the wire comes in should I be able to move that by hand?     
  • Val
    Val Member
    Here is the picture for any reference  


  • Jon B
    Jon B Administrator
    Move WHAT by hand?  Are you saying that the terminal on the switch is loose?  Or that the wire is not secured to the terminal?
  • Val
    Val Member
    the wire is secured but I can move the terminal
  • Jon B
    Jon B Administrator
    The terminal would be "suspect", then.  can you get the switch out to work on it? Perhaps if you remove the four screws around the perimeter of the cover, the cover can be removed and this will reveal what's going on inside the switch.

    I'm sure there are electrical tests you can put on this switch to see if it works.  Depending on how it's wired, when it reaches a certain speed it should either a) open or b) close a circuit.  So if there is a safe way to jack up the rear wheels and run the car at about 30 mph, and put a continuity tester across the terminals, you should notice something happening at 25 to 35 mph.  If the switch is working.

    Here's a guy on the internet that talks about testing the switch.  He's talking about Ford overdrives but they're all Borg Warner!  https://www.ctci.org/gilsgarage/OverdriveGovenorTest.php

    If you discover that your switch is toast and you need another one, there are several avenues to take.  First, send out e-mails to some of the Hudson vendors who advertise in the WTN, asking if they have any (send a photo and list any part number markings on the case, to help them identify the right one).  They'll be used switches but will probably work.

    Ebay is another avenue. Here's a "Hudson" NOS switch but the guy doesn't know which year it fits:  http://www.ebay.com/itm/Autolite-TGA4002-HUDSON-Overdrive-Solenoid/311925900588?epid=1351329984&hash=item48a03b852c%3Ag%3ASfYAAOSwsQVZeqAV://
    It looks like yours.  Here is a Nash switch, also NOS and cheaper:  http://www.ebay.com/itm/NOS-1947-Nash-Transmission-Governor-OEM/191822723452?hash=item2ca986797c%3Ag%3Abg8AAMXQySpRWsmF
    You'll just have to find out if it interchanges with your Hudson.

    In the end, your problem may not lie with the governor switch at all.  You might just have a loose wire in the circuit somewhere.  Check your shop manual, it might have a troubleshooting section on the overdrive.
  • Val
    Val Member
    Thanks Jon for all the info, I just had installed (Trans) at Dr Doug's and it worked fine on the 5 hour drive home. So I would think it should still work. I will check though with the screws removed to see if something is loose.
  • Val
    Val Member
    Also not sure mine is a Borg warner
  • ernie28
    ernie28 Expert Adviser
    Check that the governor has not filled with oil. If so, clean out and reassemble to see of it is all go again. 
  • Val
    Val Member
    Ernie28 do I do that by just removing the 4 screws?
  • dave11
    dave11 Expert Adviser

    You may want to ensure that you have a source of current going to the governor switch. The source is supplied from the generator , not from the battery, so if the generator stops charging for any reason the OD will not work. You did say yours is a 39,... I believe. On the 52 stepdown such as I have there is a charge light on the instrument panel, when that light comes on the OD will not engage 

  • Val
    Val Member
    Yes its a 39 and does have the charge light on the dash
  • Jon B
    Jon B Administrator
    Val, why does one of the two terminals on the governor switch seem to have no wire attached to it?
  • ernie28
    ernie28 Expert Adviser
    Val, I disconnected the terminals and remove the whole unit to empty the oil and clean up but yes the back cover needs to be removed. 
  • lostmind
    lostmind Expert Adviser
    Why not call the man that installed it and get his opinion?
    It was working when you left there.
    Maybe there is a fuse in the system he could direct you to.
  • onerare39
    onerare39 Expert Adviser, Member
    edited August 2017
    Val,

    I agree with lostmind. Stop and call Doug before you do anything.

    John Forkner


  • Val
    Val Member
    Jon B, I don't know would have to ask Dr Doug, ernie28 Thanks for the info. Lostmind and John Forkner  Have spoken with Doug and he gave me some advice and an easy test to do. Thanks to all who have given advice and help in this matter. I greatly appreciate it.     
  • Val
    Val Member
    Got the Overdrive working again. The Good Doctor was a tremendous help in he sent me both a new solenoid and new relay. The relay did the trick.