240 Odometer gear replacement (with pictures)

[towerymt]

This is a pretty easy job but I've been putting it off for a long time. My car is a '92 240 with a service light reset and tachometer. This car uses torx screws, but earlier ones used phillips head instead.

Step 1, remove the cluster. Two knobs left of the cluster pull straight off. Pop the switch plate out with a pocket screw driver. Pop off the blanks or gauge bezels to the right of the cluster. Remove 4 phillips head or torx screws that secure the cluster to the dash.

Pull the cluster forward til it's against the steering wheel. You may need to remove the steering column panel on top, two screws (phillips or torx). On my '92, there's a round plug, a half-round, a red/yellow connected at the lower corner on the passengers side, a red/white tach signal wire plugged to #1 on the tach, a small plastic connector on the speedometer circuit board, and a pink/grey wire with male disconnect plugged in just beneath the tach (or large clock).

Step2, remove the speedometer from the cluster. Remove the seven screws from around the edge of the cluster and remove the four smaller screws on the back of the speedometer.

Step 3, crack open the walnut. Remove the two small screws and carefully lift the circuit board up, being mindful of the small wires that connect it to the speedo.

If a broken gear is the reason your odometer doesn't work, it'll be obvious. Remove and replace the smalll gear. Make sure it spins freely. A dab of sewing machine oil wouldn't hurt. In mine, the broken gear was stuck to the shaft, but it hadn't spun since last October. Once freed, it spun easily, so I assume it's just from sitting in the same position for so long.

Put the grey plastic disc back inside the odometer and carefully seat the circuit board back in place, making sure the black gear on the shaft meshes with your new gear.

Replace the two screws and slide the speedometer back into place on the board. Be sure that these small connectors on the odometer circuit board line up with the cluster circuit board.

If you don't have a service light, then I don't think you'll have these. Definitely were not there on my '87. Drop the board back into the cluster, making sure the trip odometer reset lines up, and replace all 11 screws.

While it was apart, I cleaned the face of the cluster and the black bezel that was filthy. All clean and back together.

I've reinstalled my cluster and test driven the car...odometer works again.

 

[bwiley240sedan]

Nice one! Much better photos than the black-and-white copy that usually comes with those gears.

 

[towerymt]

Bought a couple gears from a member here: http://forums.turbobricks.com/showthread.php?t=303803

 

[cleanflametrap]

Be sure you retrieve the broken teeth. Might be obvious to you, but plenty have been bitten.

 

[towerymt]

Six months later, it still works. I reset the trip odometer (while stopped) at every gas fill up, too.

 

[cleanflametrap]

Hey, that's great. You did good work.

As for the trip reset, I use them unabashedly on all those cars with new gears in them. Even when rolling. The new gears aren't made of mush, no matter whose you buy.

 

[volvo?]

I bought one from ipd and my odometer still does not work. It works if I put my old gear back in until it makes it to the missing tooth. Any ideas?

 

[PardoR]

I bought one from ipd and my odometer still does not work. It works if I put my old gear back in until it makes it to the missing tooth. Any ideas?

The same case on my odometer... I bought the single gear from ipd, replaced the older gear (it was in good shape, not broken teeth) and still not works! Maybe a lack of lube?

 

[BradC]

If you are going to lube them, use some silicone grease. It's the petroleum based lubricant on there from the factory that has damaged the plastic over the long term.

 

[blkaplan]

I had to blow my odometer out with compressed air as i believe the old teeth were logged in the works somewhere...

 

[JamesBond00797]

Just happened to be replacing mine, as it works intermittently on a temperature basis, and I see a little copper piece sticking out near the trip reset button. Anyone happen to know where it goes and how it fits?

 

[sxepink]

Just happened to be replacing mine, as it works intermittently on a temperature basis, and I see a little copper piece sticking out near the trip reset button. Anyone happen to know where it goes and how it fits?

In case you haven't figured out yet, that copper piece is just there to hold the trip reset rod in place, mine looks like this:

 

[504]

The same case on my odometer... I bought the single gear from ipd, replaced the older gear (it was in good shape, not broken teeth) and still not works! Maybe a lack of lube?

Replace both of the gears. Also look for the missing bits and hit the speedo with compressed air.

 

[towerymt]

11 years later and that odometer is still working, up to 257,000 miles now.

 

[sxepink]

11 years later and that odometer is still working, up to 257,000 miles now.

Great stuff! Thank you for the write up.

I got my 245 on 7/11 this year at 221,925 and drove it for 2 weeks with it stuck (god knows for how long it has been broken). So when I replaced the gear I rounded it up to 222K and the new gear from IPD fixed it (I tried 3d printing one first but even tho it fit, it didnt fix the odo).

While I was in there I had some success cleaning off the pitted cluster and gauge faces with paper towels and 91% isopropyl alcohol and painted my faded needles with some pinstriping paint i have.

Here's a before and after