DB26 Posted October 30, 2018 Share Posted October 30, 2018 Hello everyone, While driving my '26 the other day I noticed the speedometer working rather sporadic. Above 15 MPH or so it will drop down to 0. I made a video of what I found when I removed the speedometer cable. I have bench tested the speedometer and it works fine. Link to comment Share on other sites More sharing options...
Spinneyhill Posted October 30, 2018 Share Posted October 30, 2018 (edited) I think you should remove the cable inner to check it for twist. I further think you should bench test the speedo by hand. I believe it has a die-cast body. At 90+ years old it is probably swelling (disintegrating, basically). My Dodge 8 speedo is. This causes the speedo body to tighten up on the cable. Erratic speeds follow, as does a twisted cable inner, which will eventually break. After you have proved these parts to be OK, then it is time to perhaps suspect the speedo drive gear. At the moment, you are lifting it and turning it. It should turn but don't lift it to check. There may be some backlash. I am assuming you have enough oil (not grease) in the gearbox to adequately lubricate the gear? Edited October 30, 2018 by Spinneyhill (see edit history) Link to comment Share on other sites More sharing options...
DB26 Posted October 30, 2018 Author Share Posted October 30, 2018 Thank you for the thorough response. I just recently added new 600w oil to the transmission and it is at the proper level. I will do some further testing. Link to comment Share on other sites More sharing options...
Wheelmang Posted October 31, 2018 Share Posted October 31, 2018 Just watched your video. If memory is correct, that drive that you were moving with the screwdriver should only move when the transmission is rotating. You may want to pull the drive gear assembly and make sure nothing is stripped, broken or worn in there. Link to comment Share on other sites More sharing options...
DB26 Posted October 31, 2018 Author Share Posted October 31, 2018 I was thinking the same thing. I coundnt image why it would be loose. And the transmission is in 1st gear during the video. So even more of a reason for it to be immovable. Link to comment Share on other sites More sharing options...
Wheelmang Posted November 4, 2018 Share Posted November 4, 2018 I had a couple of spare gears but just took a look at them and both are worn. Into the scrap metal bin! Link to comment Share on other sites More sharing options...
DB26 Posted November 4, 2018 Author Share Posted November 4, 2018 Darn. This may be the case with mine. I took the Dodge out for a drive just a few minutes ago and now my speedometer doesn't work at all. I must've finished if off when I took it apart. I'll take the gear out this week and post my results. Link to comment Share on other sites More sharing options...
Spinneyhill Posted November 5, 2018 Share Posted November 5, 2018 Are you sure the speedo is OK? Link to comment Share on other sites More sharing options...
trini Posted November 5, 2018 Share Posted November 5, 2018 The easiest way to test your speedometer is to disconnect the cable from behind the speedo meter. With the rear wheels jacked up, blocked safely , run the engine in gear and see if the cable turns. The drive from the tranny could be worn. It may be better to check the drive gear in the tranny and take it step by step. Pull the cable out and inspect. Next step would be remove speedo from the dash , hold it in your hand and see if it works while the engine is running in gear. remove the housing and look for felt covered oil holes. The parts inside of the speedometer are very delicate. Part with the numbers that shows through the window turns by some kind of magnet connection and floats on an axle which must be oiled and must move, rotate, freely. Spin it by hand and if working properly it will always come back and rest on zero at the window. If I remember correctly there is a micro adjustment screw . The " counter" adjusting thumb screw could be suspect for lack of lubrication . If the cable is new it may be fractionally too long . It will fit but the forward pressure will cause problem. 1 Link to comment Share on other sites More sharing options...
DB26 Posted November 5, 2018 Author Share Posted November 5, 2018 Thanks for the advice. I will continue to work on this project this week. Link to comment Share on other sites More sharing options...
DB26 Posted November 10, 2018 Author Share Posted November 10, 2018 Did some more digging tonight. I think maybe the speedo gear is stripped. Here is another video: Link to comment Share on other sites More sharing options...
Wheelmang Posted November 10, 2018 Share Posted November 10, 2018 Your gear looks like it is rotating on an eccentric shaft or bore. Are the teeth on the gear worn or is it the bore on the gear. Link to comment Share on other sites More sharing options...
DB26 Posted November 10, 2018 Author Share Posted November 10, 2018 (edited) I'll have to study it a little more. Does anyone know for certain that the speedometer gear is removeable through the top? Edited November 11, 2018 by DB26 (see edit history) Link to comment Share on other sites More sharing options...
DB26 Posted November 12, 2018 Author Share Posted November 12, 2018 Another update for today. I took the a Dodge for a drive a few minutes ago and had the speedometer disconnected, but the cable connected to the transmission. As I was driving, I witnessed the cable turning. I grabbed the end of the cable with my fingers and was able to stop it from rotating with very little effort. Link to comment Share on other sites More sharing options...
Wheelmang Posted November 12, 2018 Share Posted November 12, 2018 I can’t remember if it is a key way drift pin or something else that holds the gear in place but certainly sounds like something is stripped worn or sheared off. 1 Link to comment Share on other sites More sharing options...
Ron Lawson Posted November 12, 2018 Share Posted November 12, 2018 I can see in your video that the teeth on the gear are stripped 1 Link to comment Share on other sites More sharing options...
DB26 Posted November 13, 2018 Author Share Posted November 13, 2018 (edited) Okay then I am putting this one on hold until I can locate a new gear. Thanks everyone! Edited November 13, 2018 by DB26 (see edit history) Link to comment Share on other sites More sharing options...
Spinneyhill Posted November 13, 2018 Share Posted November 13, 2018 Try to find out why it is like that too. Something has caused it to break or strip or whatever has happened. There may be something else to fix while you are on it. 1 Link to comment Share on other sites More sharing options...
dwollam Posted February 19, 2019 Share Posted February 19, 2019 You have to pull the transmission top off. Then you can unscrew the large nut on the top side of the speedo drive. Find a good used one and swap out the complete drive. Maybe Myers or Romar have new gears. Let me know if you can't find the parts. I may be able to dig some up. 1 Link to comment Share on other sites More sharing options...
DB26 Posted February 19, 2019 Author Share Posted February 19, 2019 12 hours ago, dwollam said: You have to pull the transmission top off. Then you can unscrew the large nut on the top side of the speedo drive. Find a good used one and swap out the complete drive. Maybe Myers or Romar have new gears. Let me know if you can't find the parts. I may be able to dig some up. I had shelves the project, but I might tackle this sooner than later. I was under the impression I had to remove he transmission from the car. I have a few other projects going on right now that should be done with in a the next few weeks. I will let you know if I need your help with a part. It would’ve nice to see just how far under the speed limit I’m going. Link to comment Share on other sites More sharing options...
Mpgp1999 Posted May 6, 2022 Share Posted May 6, 2022 Any updates. I am having the same problem. Link to comment Share on other sites More sharing options...
cutdown Posted May 6, 2022 Share Posted May 6, 2022 (edited) I have just done up my gearbox. Final check was the speedo drive, and to my surprise, I found the bushes etc were very badly worn, probably enough to disengage the gear. I stripped it, machined down the shaft to get it true and made up and fitted new bronze bushes. Having never driven the vehicle at all, I never experienced what you have found. Next job will be to check out the speedo. It could never have worked as the inner cable that came in the car was far to short. New pc of 5/32 " x 18 3/8 " long cable on the way to me and I will re-solder the ends on it when it arrives. Edited May 6, 2022 by cutdown (see edit history) 1 Link to comment Share on other sites More sharing options...
Mark Gregush Posted May 7, 2022 Share Posted May 7, 2022 Did you know there are left and right twist speedometer cables? Twist goes opposite of rotation, so it does not try and unwind. 1 Link to comment Share on other sites More sharing options...
cutdown Posted May 7, 2022 Share Posted May 7, 2022 35 minutes ago, Mark Gregush said: Did you know there are left and right twist speedometer cables? Twist goes opposite of rotation, so it does not try and unwind. Had not thought of that, but I asked the man to send me a length of the same one that was sold to our Whangarei member. Its anticlockwise looking into the speedo, so I will check it out when its gets here. Couriers are very slow at them moment. Took a week [ after ringing up on the 5th working day to find out where it had got to ], for my front spring eye bushes to arrive from Auckland. The cable I took out had a r/h threaded look so was the right type. Link to comment Share on other sites More sharing options...
Mpgp1999 Posted May 7, 2022 Share Posted May 7, 2022 (edited) 2 hours ago, Mark Gregush said: Did you know there are left and right twist speedometer cables? Twist goes opposite of rotation, so it does not try and unwind. I recently learned that because I started working at an antique automotive restoration shop. They specialize in early brass cars and nickel. I have learned a lot. Because I am beginning to work on other peoples antique cars I figured that I need to get my car in perfect running condition. Why would you trust me to fix your antique car for 70 bucks an hour when I can’t fix my own. Edited May 7, 2022 by Mpgp1999 (see edit history) Link to comment Share on other sites More sharing options...
Mark Gregush Posted May 7, 2022 Share Posted May 7, 2022 2 hours ago, cutdown said: Had not thought of that, but I asked the man to send me a length of the same one that was sold to our Whangarei member. Its anticlockwise looking into the speedo, so I will check it out when its gets here. Couriers are very slow at them moment. Took a week [ after ringing up on the 5th working day to find out where it had got to ], for my front spring eye bushes to arrive from Auckland. The cable I took out had a r/h threaded look so was the right type. As short as the cables are, might not be an issue anyway. Link to comment Share on other sites More sharing options...
DB26 Posted May 9, 2022 Author Share Posted May 9, 2022 I never did fix that problem. Link to comment Share on other sites More sharing options...
cutdown Posted May 10, 2022 Share Posted May 10, 2022 My speedo was stuck. I managed to get it apart. :Lubricating the driven shaft only allowed it to turn stiffly. I rang the supplier of the cable and they were able to sort the speedo out for me so i sent it to them this morning. They had not done the cable yet so will include the new cable with the speedo when it is returned to me. DB26. What are you going to do about your problem. No point in not fixing it. We need to know how you fixed it otherwise what was the point in asking on this forum. Link to comment Share on other sites More sharing options...
Mpgp1999 Posted May 10, 2022 Share Posted May 10, 2022 On 5/9/2022 at 3:01 PM, DB26 said: I never did fix that problem. Darn. I am not sure I have not taken it out. Can it be removed without removing the transmission top. Link to comment Share on other sites More sharing options...
cutdown Posted May 11, 2022 Share Posted May 11, 2022 No. You have to take the top off the tranny. The nut on top holds the drive in place, but it is inserted from underneath. Eazy Peazy. Link to comment Share on other sites More sharing options...
cutdown Posted May 19, 2022 Share Posted May 19, 2022 (edited) So now I cant seem to find any of this speedo cable in NZ. Have been supplied the clockwise version but would rather use the correct version. I need a length of 492 mm, 4mm speedo cable for anticlockwise driven speedo. To ID the cable, the outer wire is spun in a clockwise direction, so that when rotated anticlockwise, it would have the tendency to wind up. Spun the other way, the outer spun wire would tend to unwind, and jam. Many thanks Dereck PS I put this request in the buy/sell part of this forum as well. Edited May 19, 2022 by cutdown correction (see edit history) Link to comment Share on other sites More sharing options...
cutdown Posted May 21, 2022 Share Posted May 21, 2022 Got it sorted. The Auto Sparky sold me clockwise spun cable, which is the correct type for anticlockwise drive. 2 Link to comment Share on other sites More sharing options...
Recommended Posts
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 accountSign in
Already have an account? Sign in here.
Sign In Now