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I noticed that both odometer numeric counters stop working at times. When cold they will work normally but after a while when the bottom row try to switch 9.9 to 10.0km, or 19.9 to 20.0km everything freezes.
I suspect the large gear slipping on the shaft.
Can I use super glue there ?
Thanks for bringing your experience.
Roland
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It might work for slipping gears, just hold it with the gear hanging down so if you apply too much gravity will take it away rather than into the internals.
Dan
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I haven't checked in for quite awhile, but since 2014 seems a bit long.
Hi RolandP,
You're in Quebec, if my memory is correct (can't access your profile).
Yes, the gear loses its grip. It may even be cracked. I used a spot of blue thread locker and put a small o-ring on its "shoulder".
--
1980 245 Canadian B21A with SU carb, M46 trans, 3:31 dif, in Brampton, Ont.
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Yes, it is the pot metal gear that is loose on the steel shaft.
I found an other working cluster in my spares parts, it is from my son's car we took apart about 15 years ago. It is almost same mileage so I put it in.
In the following weeks I will try to inject super glue with a hypodermic syringe and see if it hold. I will let it run a couple of hours at 60mph with a hand drill on reverse. If it hold, it will be ready to go back on service if needed.
If the super glue does not hold I will try your method of reversing the shaft.
Thank you all for the help.
Roland
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Was thinking more of a sewing needle.
Before deciding to reverse the shaft, I thought I'd try using a sharp chisel to knurl the worn spot a bit, but both ideas necessitated the finicky task of disassembly. That's the fun part!
--
Art Benstein near Baltimore
One tequila, two tequila, three tequila, floor.
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Finally had some time to put on this problem.
Thanks to you I found the problem was the pot metal gear slipping, it never occured to me that this would be possible.
In the mean time I found two more defective odometers in my spare parts; one with a plastic gear missing one tooth, the other one having the pot metal gear slipping on the shaft.
As you did I pushed out the shaft and reversed it so the pot metal gear would be thight on a unworn part of the shaft. And I did not want to go back there so I did an extra touch. I put the pot metal gear on a flat steel block and using a 1/4inch pusher I gave it a mild hammer blow in the center so the hole would be smaller, I hoped.
I pushed the shaft back in its position using a vice. Using a variable speed drill on reverse I could confirm the km counter is working ok.
Now I have two odometer spares for this 1982 volvo that has more than 325k miles (525k km), burning no oil (unbelievable). It is now with a front windshield that has the chrome trim replaced with a hand applied black urethane strip, a m46 overfilled transmission and running with a modified electronic ignition from a 1982 b23e. This is a B21A with carburator.
Thank you again Art to put me on the right track.
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OH, and I tried rhe super glue using a diabetic type of syringe. Very fine nnedle by the way.
I ended up gluing the pot metal gear to the pot metal frame just beside. Bad idea.
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If I'm thinking of the correct odometer, way back when I had both odometers begin to not function and it was the little white intermediate gear between the two odometer end gears having slid out on its shaft a bit. As the little gear moves out and is only barely catching the teeth, I think it was the trip gauge that started to misbehave first. Simply pushing the little gear firmly back on the shaft was the fix and I never had the problem again. If they both misbehave together then your suspicions are probably correct, the large main gear. Normally about 1/8" of shaft is sticking out beyond the little white gear, so before you button everything back up, double check to make sure it's pushed on all the way. If it was a missing/damaged tooth on the small cog gear inside the large gear then I would expect it wouldn't be an intermittent problem. Applying glue with a toothpick or whatever rather than straight from the tube will help prevent over-runs.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
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Hi,
Yes I think you could try super glue but be very careful upon applying them as they are very thin and can run off to other places that you will not want it too. They are so clear that it’s very near impossible to follow the flow. One drop can turn into a flood in my experience of using those glues.
What you have going on with the gears is age of the material decomposing for the most part. Plastics are a petroleum product of molecules of a lattice structure as so do metals but metal has a grain structure whereas petrochemicals are more gaseous by nature.
The material has most like shrunk increasingly with time that accumulates internal stresses in the material until it micro cracks.
Originally the materials are made to a size that includes a press fit onto those shafts you are referencing as not turning except under certain conditions.
You will want to fill those micro cracks but it will not tighten the material back up.
What you will end up doing is creating more contact surface to engage the shaft.
That can be fine and dandy, if you have the space away from any other components that don’t have to spin freely.
In other words, you want to weld it to the shaft but you have to have room for a fillet material to engage the shafts surface.
In the case of the later electronic speedometers, 1985 on, the gears crumble and replacement is the only option. I made my own out of a piece of Delrin that has a better molecular structure than whatever junk stuff VDO or other vendors used in all the years of Volvo’s speedometers.
Plastics have evolved tremendously in the years since to be almost a miracle material in proper applications.
With your 1982 speedometer it has been like some of NASA’s space programs probes. It has gone farther than they ever intended.
As a fact with my 1978 speedometer the shafts wore out the housings journals.
Instrument clusters didn’t and still don’t come hermetically sealed today because their not mechanical at all.
Heck, they don’t even do headlights that way anymore.
Your headlights are still $10-15 for a swap out. My 1984’s four Beamer are free or a dollar in garage sales!
The newer headlights didn’t start cost much more to make than the originals back then either but marketing styles, over rules logic, if there’s is any?
The replacement bulbs in them don’t cost squat to make by comparison of glass and energy of the complete sealed beams.
Let me say …. they’re how much now? 😳. Duh? 🤔
Never mind how the hazed up or water filled the plastic housings get to be, before the bulbs burn out.
Yep, try super glue ….. carefully!
Nothing to lose as it’s not working already!
I peened the journals with an adjustable strength automatic center punch gadget and got a few more years.
The 1978 is probably 30 grand behind the actually full mileage but the speed part still works to the local stores.
I watch it as a reference but share my eyeballs with the two other gauges. Oil changes are color or time intervals. Todays oils are really good.
Phil
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