Firstfives.org

Hey guys:

I recently took a trip from my place (San Carlos, CA) to Santa Rosa and thought to check my gas mileage.

My odometer showed a total of 102 miles traveled, while google maps confirmed something closer to 175 (some side roads). Needless to say my gas mileage first came up at 7.73 mpg, while the actual was 13.2 mpg. Both suck, but that is not the issue yet.

So, I have been doing some odometer and speedometer testing.

Speedometer reading/GPS

-40/42
-50/53
-60/63
-70/73
-80/83
-150/153 (just kidding)

Odometer reading/google maps

-102/175
-30/31.7
-14/31.1
-32/32
-5/5
-10/10
-10/10

It appears that my speedometer is reading a bit low. My understanding is that manufacturers erred in the other direction. What could be the cause of this? My rear tires are stock (195/70 14)...fronts are 185/70 14.

My odometer seems to be mostly accurate and sometimes totally off! My gut tells me that I may be dealing with a broken tooth somewhere. Any ideas?

I was thinking more about it and think that these observations are relevant. The trip meter and the odometer seem to be in synch...whether in error or correct. So the problem must not be with one of those individually. Also, I do not see an issue with the speedometer and I am guessing that the whole assemble is run by one cable...so the transmission end of the cable must be driven correctly (though the mph is reading too low).

I've been trying to think of something besides having you send it back again but that is all I can think of. Call me when you get a chance and we can go over the numbers again. I will have more time tomorrow and next week.


Jeff
757-593-3478

Blaise wrote:My odometer seems to be mostly accurate and sometimes totally off! My gut tells me that I may be dealing with a broken tooth somewhere. Any ideas?

Yes - you are right - you have a broken gear in the odometer. I presume that you haven't changed your differential - there can raise a mistake also, but as you say - the problem appears only sometimes.

I have a similar problem years ago. When I opened my odometer - I found a little white plastic gear which was split and that was the reason it was turning over its shaft almost freely, without moving the odometer digit wheels. Your gear could be split also or just turn freely without splitting.

Maybe in your case this gear isn't moving so freely but time to time it does.
The only thing you can do if you want to repair the odometer - is to stick the gear to the shaft in two steps. The first is to coarsen the shaft in that place, where the gear stands and then - the second - to glue the the gear to the shaft.

Alexander

It looks like you are hooked up with Jeff. Stay that way.

I second the Jeff Caplan situation. He has repaired a large number of first fivers odometers, including mine. Stick with Jeff.

I may be getting my fixes mixed up. I was working with John Williams on a different issue and sounds like I am mixing them up.

Looking at your numbers, I would say it's one or two gears need help inside. Check the nylon gear for cracks and also the thin grey metal gear for slippage. Both gears must be tight on the shaft. If you push on the grey metal gear and the numbers turn, it needs to be replaced.

Call me


Jeff
757-593-3478

Odometergears wrote:I may be getting my fixes mixed up. I was working with John Williams on a different issue and sounds like I am mixing them up.

Looking at your numbers, I would say it's one or two gears need help inside. Check the nylon gear for cracks and also the thin grey metal gear for slippage. Both gears must be tight on the shaft. If you push on the grey metal gear and the numbers turn, it needs to be replaced.

Call me


Jeff
757-593-3478

Thanks for all of the input guys.

Jeff, you must be confusing me with someone else, as we have not worked together. Thank you for stepping up to take responsibility

I have not seen the inner workings of the odometer, so not sure what is involved. It does sound like I need to get in there to find the problem.

What is involved in removing the speedometer cluster? I see some instructions here....but what fasteners need to be removed?

http://www.firstfives.org/faq/dash/dash_removal_faq.htm
http://www.bmwcarclub.org.ph/forum/show ... php?t=4074

I just spoke with Jeff Caplan. It sounds like one or more of the internal gears may be slipping on it's shaft.

Jeff explained that he sells these gears and would also install them free of charge (for first fives members).

Thank you Jeff for taking the time to help me.

I will try to get in there in the near future and take a closer look. I will also adjust the speedo at that time.