Odometer & Trip Odo questions - PeachParts Mercedes-Benz Forum

rrgrassi · #1 02-11-2009, 09:32 AM

We all know that the failing odometer is a fact of life for our cars. My trip odo has been stopping at xxx.9 for the past few years, but you could see the numbers "twitching". Resetting it brought it back to life for a bit.

Now, no more twitching, and with no twitching, the mileage odo does not work. When the trip odo starts spinningagain, soe does the mileage odo.

Any ideas on what would bind up the trip odo, that then make the mileage odo stop?

I plan on taking the cluster out this weekend. I do have a speedo from an '85 to go with the rear diff swap. If I go that route how do I roll up the mileage to match?

Thanks!

#2 02-11-2009, 12:00 PM

Quote:

Originally Posted by rrgrassi

Any ideas on what would bind up the trip odo, that then make the mileage odo stop?

Slipping gear. Diesel Giant has a great guide on repairing it.

carnut · #3 02-11-2009, 12:33 PM

There is a gear on a serrated shaft between the odo and tripmeter. That gear will, over time, loosen on the shaft. What I did was slide that gear over to one side, put super glue on the serrated area and slide the gear back in place. What causes this is resetting the trip meter while the car's in motion. The gear eventually works loose on the shaft. Try www.dieselgiant.com for the write up.

rrgrassi · #4 02-11-2009, 12:50 PM

Ok, cool. I was wondering what caused the trip odo's binding.

I have read the Diesel Giant repair.

rrgrassi · #5 02-12-2009, 09:42 AM

Now, can any one tell me the best way to "roll up" the odometer to a more realistic reading? I need to bump it up by about 500 miles.

Also, what type of lube oil/grease should I use?

Thanks!

Stevo · #6 02-12-2009, 09:50 AM

All I can tell you is my son in law somehow managed to lose the wheels while "fixing' is broken odo on his 116. The drill bit came out dumping the wheels on the work bench. He couldn't figure out to get things back together without setting the odo back to 'zero miles"

awsrock · #7 02-12-2009, 09:57 AM

Quote:

Originally Posted by rrgrassi

Now, can any one tell me the best way to "roll up" the odometer to a more realistic reading? I need to bump it up by about 500 miles.

Also, what type of lube oil/grease should I use?

Thanks!

I just manually rolled the odometer up to where it should have been. Basically, you can turn the gear if you put the rod in all the way, but just before the gear meshes with the other gear. It took a while, but it worked. Is that too vague?

rrgrassi · #8 02-12-2009, 11:10 AM

Not vague at all. I work on model railroad stuff, so I understand. I also learned to work on stuff like that over a box lid to catch small, runaway parts.

Jeremy5848 · #9 02-12-2009, 11:13 AM

A drill motor or Dremel motor works great provided they run in the direction you want to go, of course.

rrgrassi · #10 02-12-2009, 11:33 AM

A drill is reversable, my dremel is not.

What RPM is the speedo cable spinning at say 70 mph? My dremel goes up to 35,000 rpm.

JimFreeh · #11 02-12-2009, 11:41 AM

Be very careful with the drums.
The numbers are easy to smudge.
This makes it harder for the odo rollback crowd.

I use a dental pick for some aspects of my speedo repairs, helps to separate and spin the drums without touching them.

I also would vote to reset the odo to match your actual milage.

Jim

rrgrassi · #12 02-12-2009, 12:04 PM

I do not have any dental tools. I do have plenty of tooth picks though.

Brian Carlton · #13 02-12-2009, 01:19 PM

Quote:

Originally Posted by JimFreeh

Be very careful with the drums.
The numbers are easy to smudge.
This makes it harder for the odo rollback crowd.

Is it not possible to clean the white lettering on the drums.........or will that surely wipe the numbers? I was thinking of simple green..........but, it sounds like that might be a bad idea?

Palangi · #14 02-12-2009, 09:10 PM

Quote:

Originally Posted by rrgrassi

Now, can any one tell me the best way to "roll up" the odometer to a more realistic reading? I need to bump it up by about 500 miles.

Also, what type of lube oil/grease should I use?

Thanks!

When you have the parts off the back of the speedo (following Diesel Giant's procedure) you can just spin it ahead by rolling the brass gear with your thumb. 500 miles is only about a minute or so at thumb speed.

bobodaclown · #15 02-12-2009, 11:51 PM

Geeze 500 miles out of 250000 is 00.2%... HMMM.. are the odometers even that accurate.. I'd just let it go.