Odometer stopped working, 100kms after replacing gear.

[Volhv]

I just figured out why. The big middle gear moves outboard and binds.

Made a video demonstrating the problem.
Late 944 odometer gear shifting - YouTube

Installing a washer before the c-clip will fix this.

[Gawernator]

I wonder if this is what happened to me..... thanks!!!

[CHICKS]

Whoa cool, mine kept failing after a few hundred miles too. Thanks for the heads up, I'll give this a try.

[Bukowski]

What are the numbers of teeth on - I presume - the replacement gear at the left end of the assembly - the one everyone replaces?

That would be the smaller/inner gear and larger/outer gear?

How many teeth on the gear that touches the replacement gear?

Are any other gears replaced?

Did you apply lubricant or clean any off?

what specific year is the car?

[Volhv]

It's an 86, so the oval dash.
Far left gear was replaced to do stripped teeth.


Lubricated the gears with instrument oil.
As far as number of teeth.... I never counted.

[Bukowski]

Originally Posted by Volhv

It's an 86, so the oval dash.
Far left gear was replaced to do stripped teeth.
...

Lubricated the gears with instrument oil.
As far as number of teeth.... I never counted.

there are a couple sources for this info, and I don't have Pelican's listing in front of me, but I think Pelican sells from odometergears.com and I think odometergears.com is what I am remembering:

Odometer Gears - Porsche - 944 85.2-91

if that's the right year and country for your car, then:

"There are multiple tooth count options that can and will be installed in this odometer. You will need to count the teeth on the old gear before ordering. The outside gear will have 20 teeth and the smaller inner gear between 21 or 22. {If you cannot count the teeth on the main gear then count the teeth of the next gear that it meshes with. If your tooth count is 49: 20x21, 48: 20x22}"

... I can tell you I called Pelican about this, and they made for a super easy exchange of the incorrect gear for me after I got the incorrect gear. I can't recall the details, which I did write down, but the gear choice was actually a coin toss in the end I think because of what was known about what the original gears were, not because I didn't count anything. I also called someone at odometergears.com and the person - perhaps the owner, I forget his name unfortunately - were exceptionally helpful and actually fun to discuss the gears with.

I can't say the slipping you show will no longer happen even if the correct gear is there.

[Volhv]

Thanks, Now I see what you mean.
I got the euro spec KPH gear from Rennbay.
Unfortunately I was unaware that there may be different tooth numbers.
If it stops working again, I'll have to take it apart, and do some counting.

[Volhv]

It stopped again. 184 kms this time!
Figured out one more problem.
The new gear I got has 4 circular raised areas on its face. This is where the sprue and risers were. Unfortunately some material was left behind when they were removed, and that binds against the gear that I put the washer on.
Sanded them down smooth, so let's hope for the best. This it the 4th time I've taken the cluster apart.

Yet again I forgot to count the teeth. Hopefully I never need to.

[Volhv]

It's been about 8000 Kms, so far so good!

[Volhv]

Crap, it stopped working again. But it was fine for more than a year and a half. Maybe about 20 000 kms. I'll have to look at it AGAIN! This is awesome.......

Oh, and I never did touch the trip reset. Maybe i'll disconnect it, and re purpose that switch.

[kdjones2000]

Check the little "paddles" on the gears between the actual counters as well.

On my first ODO some were chipped, which allowed the big wheels to move around and bind, causing it to stop.

[968 GUY]

When I bought my gears from Odometergears.com, I had a bit of a problem where the odometer would not move. Took it back out, called Jeff, one of the owners, and he walked me thru the rebuild.
From what i remember, he said to make sure there were no burrs on the gears. Make sure they were perfectly clean and there was no residue or old pieces of gears, and I believe he said to NOT use any oil, as the oil actually can cause more stiction than the gears were able to overcome.
I have replaced gears on a 968 and 951 successfully.

[NBTF]

My odometer stopped working then started working after 3 weeks for about 2 days then stopped again. I was good and read up on the problem and bought my overprices new gear. I got the cluster out and took the speedo out and found my issue. This is gonna be fun fixing.

How do you split the housing?!?

[Volhv]

Still have not gotten around to looking into this odd again. ......


After you pull the needle and gauge face off, 4 screws will be revealed.
You can see one of them close to your thumb.

[mytrplseven]

Here's a thought: When I bought my barn find 951, some previous PO put white dial faces on the gauges and it somehow was the wrong one as it covered some of the warning lights. I decided to buy a similar unit with black gauges but the odo wasn't working. No big deal, since I'd done this swap before. I decided that, while apart, I wanted the mileage numbers to match the original one. In order to do that, the long pin, shown in the cracked unit above, needs to be pulled part way out to release the odo numbers so they will turn to numbers you need to show. After resetting them, the pin is pushed back in. It went in firmly and stays there.

I can see that if someone did the same thing to reset the odo for some "other" reason, they may have "ham fisted" the pin and cracked the housing. And by the way, super glue will not fix this crack. I won't last in the heat of the everday sun. A liberal coating of epoxy is the answer.

I know, I know, I'll get some post saying what I did was illegal but what I did was a "repair" and not for some nefarious reason.