Author Topic: Speedometer - why is my odometer "6" skinny?  (Read 28098 times)

Garry

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Re: Speedometer - why is my odometer "6" skinny?
« Reply #25 on: August 15, 2008, 07:01:20 »
I just think the one on the left has an eating disorder.

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seattle_Jerry

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Re: Speedometer - why is my odometer "6" skinny?
« Reply #26 on: August 15, 2008, 19:03:51 »
I'm more concerned that Scotts trip counter in the picture reads 666 and the sum of the 65930 odometer reading is 23.

I just watched the movie "23" the other day.

seattle_Jerry

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Re: Speedometer - why is my odometer "6" skinny?
« Reply #27 on: August 15, 2008, 19:12:04 »
I actually think its odd that the 9 and 6 weren't interchangeable at the factory. It would have reduced tooling costs.

scoot

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Re: Speedometer - why is my odometer "6" skinny?
« Reply #28 on: August 15, 2008, 22:11:59 »
quote:
Originally posted by seattle_Jerry

I'm more concerned that Scotts trip counter in the picture reads 666.


Ha ha ha ha!   Yes, that should concern us all I think.  I keep resetting it and it keeps stopping at that number!   I think the B-52's sang a song - something like "help! the devil's in my car..." -- perhaps it should be "help! the devil's in my pagoda...".  

It's just on 666 because it stopped working and I was resetting it and for no good reason I stopped at the 6's.
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Cees Klumper

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Re: Speedometer - why is my odometer "6" skinny?
« Reply #29 on: August 16, 2008, 08:37:58 »
quote:
Originally posted by Mike Hughes

quote:
Originally posted by scoot

...so are we saying that ALL of the 6's on the odometer are skinny for no known reason?



Essentially....Yes!  Althought I will speculate that since the numbers 6, 8, and 9 look so similar that the skinny 6 may make it a little easier by means of some Teutonic logic to accurately read the correct mileage at a glance!  In any case, they are all like that.



My euro speedo, that was put in probably about ten-fifteen years ago by a PO new to convert from the original miles speedo, has a regular size (i.e. not skinny) 6 as the first digit. I think all 6-es are normal, I'll look out for it as I rack up the km's. Maybe new speedos are normal and the original ones have skinny 6-es.
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al_lieffring

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Re: Speedometer - why is my odometer "6" skinny?
« Reply #30 on: August 16, 2008, 19:30:16 »
OK. So how technical do you want this explaination to be?

The "skinny 6" is there for the cogs on the digit wheels that allow the next power of 10's wheel to advance one numeral for each complete revoloution of the wheel to it's right.



For the operation of main odometer, on each digit wheel to the right of the numerals are 20 teeth around it's perimiter. To the left of the numerals is one single tooth, Between each of the wheels on a counter shaft is a smaller cog with 8 teeth, alternating wide and narrow. The location of the shaft with these smaller cogs happens to line up with the 6 numeral on each of the digit wheels.

In most cases, all of the wheels on the main odometer have the narrow 6. It is possible that on some speedos that the 10k's wheel could have a fat 6. The speedo shown is from a 64 220SEC and has a fat 6 on the 10k's wheel. I know that on most of the speedos that I had worked on the same skinny 6 wheels were used in all positions.

When the tooth cut next to the 6 rolls past the smaller cogs, one of the wider teeth drop down into the slot and advances the wheel to it's left 2 teeth, the wheel is then locked into place by the flat area around the rest of the perimiter contacting between two of the wider teeth of the cog wheel.

The trip odometer operates on the same basic principal but the reset function, of course, makes it more complicated.

Because the counter shaft with the smaller cogs is located above the main odometer and below the trip odometer the single tooth cut in the trip odometer wheels is in a different position. It is there, just harder to see because it is hiding in the open mouth of the 3s (if you look real close at the 3 on the trip odo in the photo Craig posted you can see it) so none of the numerals on the trip odometer wheels needed to be narrowed.

When the odometer stops working it is almost always because the grey metal wheel to the right of the 1's wheel has worked loose from the shaft that all the wheels rotate on. The brass gear to the right of the assembly rotates the shaft one turn every mile (or KM on metric odometers). The grey metal gear is a press fit onto that shaft, the plastic wheel spin free on the shaft with the white plastic cogs on the counter shaft holding them in place.


Al

« Last Edit: August 16, 2008, 20:59:11 by al_lieffring »

benzportland

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Re: Speedometer - why is my odometer "6" skinny?
« Reply #31 on: August 21, 2008, 23:20:46 »
This is actually reassuring to hear I am not alone.  I noticed my skinny 6 recently and started losing confidence......... :oops: