Easy odometer fix - PeachParts Mercedes-Benz Forum

BIGRED · #1 12-06-2003, 08:27 PM

I did some reading on the fixes talked about and I approached it a bit different.

I don't know what year of cars this will work for, but I performed it on a 83 300D.

After you have the speedometer in your hand, you will notice there are 2 gears that are on the same shaft as rings of odometer numbers, to the right when viewed as if it were in the cluster. There is one gear that is on the outside of the metal housing and one gear that is on the inside of the metal housing. The inside gear almost touches the number rings and is the source of the problem. It should be locked to the shaft, but spins freely.

On the opposite end of the gears on the same shaft, there is a brass retaining ring. This ring is held in place by friction.

You will need some type of hand tool that will mar the shaft. I used a diagonal cutter.

1. Remove brass retaining ring.
2. Pull shaft by the outside gear, just enough to get so that your hand tool can reach the shaft.
3. Score the shaft at the location that the gear normally rests. Do this by making little "bites" all the way around.
4. Push shaft back into its normal position and press the gear onto the newly scored shaft area.
5. Push on brass retaining ring.
6. Re-assemble and install cluster.

Don

Stevo · #2 12-06-2003, 10:37 PM

Right on...I use a pair of small bolt cutters to "nick" the shaft, being carefull not to use to much "snoose"

psfred · #3 12-07-2003, 11:18 AM

I just put a tiny bit of locktite on the shaft, run it sideways back and forth enough to get some under the zinc gear, and restore the shaft and wheels to normal position. Wipe up the extra, wait two minutes, job done.

Peter

BIGRED · #4 12-07-2003, 11:40 AM

I read about using a glue solution. I could not see how one could get the glue onto the shaft without getting it smeared onto the side of the number wheels and metal frame. I assumed that if the glue got onto the sides of other parts, I would create additional problems. That's why I went the non-glue route.

Don

psfred · #5 12-07-2003, 05:12 PM

Locktite is an anaerobic setting cyanoacrylate adhesive. It will not set in the presence of oxygen, so if it is only on the outside of the metal gear, it can be cleaned off with acetone and slips of paper with no harm done. Get it between the number wheels and things get more interesting!

I've not had any trouble, I've done three so far.

Peter

Stevo · #6 12-07-2003, 08:25 PM

Peter

I like it. I have done 3 with the bolt cutters and every time I squeeze those handles I wonder how close I come to the 'too much point" I will give Locktite a try next time.

Steve

gasman · #7 03-14-2004, 10:16 AM

I've taken the speedometer/odometer out of my 84 300SD because the odometer stopped working. The speedometer works fine. It started making a clicking noise a couple of months ago which varied according to the speed of the car. Now there is no clicking and odometer doesn't spin.

The speedo/odometer on my SD appears to be electronic. There is a six pin connection as well as what I thought was a mechanical cable that uses a twist friction connection (this, I thought was the cable from the transmission that turns the gears in the speedometer/odo). But after removing the back cover of the speedo/odo and examining the shaft, the shaft is fixed and connects solidly to the circuit board, so the cable that I thought was mechanical appears to be a wire that sends electric impulses to the speedometer to indicate speed and and spins the odometer.

Anyway, the shaft of the odometer and gears on it does not appear to be like the one described on this thread. The shaft of the odometer numbers is covered by a clear plastic housing that looks like if removed, everything will fall apart and I'll have a mess on my hands. Any ideas on what I can do to repair the odometer on my 300SD?

gasman · #8 03-14-2004, 12:12 PM

After studying the odometer under bright lights and magnifiying glass, I couldn't see any stripped gears, and the gears were solidly on the shafts. Initially trying to spin the gears and moving the odometer with my fingers, things were stiff and didn't want to move. After reassuring myself that everything was intact, I used more force and, sure enough, things started moving, including the numbers on the trip odometer.

I'm guessing the gear assembly and oil/grease were a little stiff and needed my finger power to get things moving again. Put everything back together and into the car, crossed my fingers, and off for a test drive. Odometer SPINS! and no more clicking noise.

There was some oil on the gears, but my question is what kind of lubricant should I use on the gears to free things up without gunking things up and causing more problems down the road?

psfred · #9 03-14-2004, 12:21 PM

I'd do the old camera/clock trick -- dilute some synthetic oil about 1 drop to 20 or so with lighter fluid and apply with a tooth pick -- just enough to cause the lighter fluid to flow into the points where the shaft and housing contact. This will "melt" any grease in there and thin it just enough to stay fluid without either causing it to get places you don't want it or drying back out.

Peter

morgantruce · #10 03-14-2004, 01:22 PM

This is a project I also need to do soon. I think it might make sense to rough up the shaft mechanically AND apply bit of LockTite. Does anyone see a problem with that?

Stevo · #11 03-14-2004, 02:26 PM

I have used LPS greasless lub on clocks and the like with good results

Mr Goodfahrt · #12 03-14-2004, 02:38 PM

I did a long post on this back in September. Another trick I found useful is the second shaft is the same as the odometer shaft and can be used to push the odometer shaft through while maintaining alignment of the number shafts.

Just be careful not to lose the small springs when you remove it.

Hope this helps...

psfred · #13 03-14-2004, 03:07 PM

If you are going to go to the trouble to remove the shaft, why not just get a new gear and put it in? Easier than roughing up the shaft since you only have to push it back far enough to clear the zinc gear.

Six of one and half a dozen of the other, and what is the likelyhood you will put ANOTHER 200,000 miles on the car?

I like the locktite because it is permanent but can still be disassembled, and you don't have to mess about with the number wheels getting out of synch.

Peter