Odometer not working-why? (1 Viewer)

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My 72 FJ40 has a 77 motor and 4 speed trans. I am running my original gauge cluster with a speedo swapped in from a donor 77 cluster. What I don't get is the speedo works fine as well as the tenths of a mile indicator. It spins all day long but never turns a mile over-any ideas?
 
Yup, there are little idler gears bewtween each numbered wheel...the are plastic, and get worn, the first wheel wears 10 times more than the second, 100 more then the third etc...
I took the worn out white wheel, and moved it to the end, and now use the next wheel in line as the 10ths wheel...
 
Mszekely has the right answer. Just be careful in disassembling the odometer and make sure that it rolls easily before you reinstall. When you reninstall, make sure the digits are all lined up properly or it will look bad in the speedo. Should work fine.

Don
 
It's not just an issue with worn gears. The lubricant used in the odometer cluster breaks down after 25 or 30 years and eventually gums up the works. When you get the cluster apart, clean everything thoroughly with a good degreaser, lubricate with a light oil and reassemble.

The hardest part of disassembly is getting a small brass bushing off the cluster spindle. It just takes a little persuasion to get it off. I cut a notch out of a piece of scrap metal and slid it behind the bushing. A few short raps on the metal piece removed the bushing without damaging the bushing itself.

Be sure to keep track of all the small pieces to make the reassembly easier.

Good luck
 
Mine was worn, the one tooth that catches the next gear was worn down, so the 10ths gear would not roll the 1's gear...either way, once you take it apart you'll see what the problem is...

hope you have small fingers : )
 
be extra careful that you dont chip the teeth off the other gears when taking it a part, thats what happened to me luckily i had a spare cluster. That plastic can be very brittle.
 
This is the bushing that I'm talking about. Without removing it, you cannot get the cluster apart. It sits under the large main gear for the odometer. On both odometers that I've cleaned, I had to remove this bushing. Do you have an easier way to get it apart?
odo_maingear.jpg
 
How much force are we talking to get this bushing off? I am stuck at that point right now. I can get two small screwdrivers in there and try to pry it off but get nothing. If I were to use pliers would scratching the bushing affect the functionality in any way? What is actually holding the bushing on preventing it from sliding right off? Any help would be great, then its on to cleaning and reassembling.

While I'm in here I just replaced all the dash bulbs with the superbrightleds. Can't wait to get it all hooked back up and check out the difference.

Thanks
 
bothersome bushing

I am also stuck trying to get the brass bushing off, no luck with prying or slipping something behind it that I can pull on. Next step pliers, but I'm worried about damaging it too as I don't have any spares around. Any other suggestions are greatly appreciated.
 
Degreaser then lubricant

I couldn't get the bushing off either. I put my entire odometer on the spindle with the bushings in a ziplock bag and filled with Oranj Peelz degreaser to cover. After maybe 4 hours soaking or half a day, I took it out and starting working the numbered dials back and forth to break up the crud in between them and let the degreaser get to more surface area. I put it back in the ziplock, resoaked the odometer again in Oranj Peelz for another 4-8 hours, took it out, let it air dry some, and then used light lubricant. I then set the odometer to 9999.9 or something like that to test the odometer when all the gears would be at their greatest load. I figure if the Odometer was loosened and lubricated enough to turn all the gears at once, it'd be good enough to use again.

I have done this to two separate odometer spindles with the bushing. The first one I did I didn't soak, twist, and soak nearly enough, and my resulting odometer still skipped. The second one I did worked fine. I haven't had cause to go back to the first one and try again, so I'd recommend really being patient and soaking / twisting / soaking over and over again until every single number is very very easy to spin.

I've got about 200 miles on the odometer since the degrease / lube and it's been fine. I don't believe my degrease and lube was as thorough as it would have been if I had disassembled, so I could run into problems quicker than others who did the complete cleaning with the bushing off. Also, I'm a little worried that because I didn't disassemble, I was not able to get the the odometer assembly completely dry, and I'm not sure if this method will promote rust in the future and really ruin the odometer.

Finally, I should warn you, I am a relative FJ40 noob -- so take my advice with a grain of salt.

Good luck. If you decide to go this route and have any success or difficulties, please post them up.
 
The good news is that after you finally get that bushing off it's much easier the next 12 or 13 times. I took mine apart and assembled it that many times before I wrapped my brain around the proper sequence for the nylon gears. Now it's smooth as silk and works great, 300 miles so far. I buggered my bushing up a little bit the first time but it hasn't affected the operation of the odometer. But my speedo is quite a ways off, like when it reads 40 I'm doing 46 according to my gps. Running 32-12.50 x 15's.
Leds are the way to go!
 
I have another trick to break up the crud.
I employed it while working on my odometer during the summer.

When the numbers are stuck onto the metal shaft, I heated the shaft with a butane lighter.
Then I gently applied pressure with a flat blade knife pushing the numbers off of the shaft. If it's still giving you grief just go through a few more cycles of heating-prying-heating-prying.

No problems to date since this refurbish and I have almost 2000 miles logged on it now.
 

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