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Tue Apr 21, 2009 11:14 am

RE: use a fork

That worked! With the speedo and face plate off, it appears that the number shaft had just slipped to the left and can no longer turn since it is out of the housing by the metal gear. I cannot tell if the metal gear is spinning independent of the shaft (which it shouldn’t).

I pushed the white worm-driven gear on the left over so that it was re-centered on the worm gear and the other end of the shaft with the metal gear was now through the housing. However, after reading
http://www.twistedlimbpaper.com/brian/vanagon/Odometer.htm , I am not convinced the shaft will stay in place.

Raynor,

Is this the problem you were seeing on yours? From your write-up it appears that your problem might have been different – the metal gear turning independent of the shaft.

After you had the metal gear out and put epoxy on the gear hub, did you need to do anything to keep the shaft from slipping to the left and out of the housing by the metal gear?

Thanks – making progress! :))

Tue Apr 21, 2009 11:20 am

RE: When you add a hard physical stop to the end where it walks out, it makes it impossible for it to move in that direction again.

I missed this before I just entered my last reply. Looks like what I need. Can you provide more details on what and how to add this physical stop? Is this a standard clip you picked up somewhere, or ? How is it attached wit the screw?, etc.

Thanks!

Tue Apr 21, 2009 8:03 pm

There's the pic. It's just made of shop bits. WYSIWYG. Get yours open and compare to the pic; you'll see what to do.

As I recall, the metal gear freewheels on the shaft. It's the plastic gear on the other end that needs tot be fixed to the shaft. It is right under the stop tab in the pic.

Can't remember for sure because my fix is still working so I haven't had to get into the thing every few months.

Tue Apr 21, 2009 8:13 pm

OK, just visited the linked-to site. He does a great job of explaining what happens. Both gears, the metal cog wheel on the one end and the worm-gear-driven plastic gear on the other end have to be fixed to the shaft. Once you do, if you add a physical stop at the end of the shaft that was walking out (it's at the plastic gear end), that will counteract the pulling force of the worm gear and keep things together.

Just make a little tab of stiff metal or even plastic, with a tiny hole in one end and attach it to the odometer plastic frame with a teeny screw.

Sat May 09, 2009 12:37 pm

Fix completed a week or so ago and tested on my dining room table. To test it, I used a speedometer cable from my old 1984. hooked one end to the back of the odometer, the other to a drill and ran it at 80 mph for 5 miles.

Reinstalled it back in the van; now the real test when I get the van back on the road and about a week.

Thanks all!

Tue May 19, 2009 12:41 pm

The odometer worked for ~67 miles, then suddenly stopped. I noticed the trip odometer was also not working. I reset the trip odometer (while stopped), and the trip odometer and the regular odometer worked again for 1 mile. When it stopped again, I tried resetting the trip odometer; alas no luck.

I have not taken it apart again yet. But what I know is the speedometer is still working, the numbers on the regular odometer are not tilted to the right like they were before my fix (as per tencent's suggestion).

Any thoughts on what might now be the problem? I'll take it apart again in a day or so.

thanks

Wed May 20, 2009 5:34 am

So I drive off this morning and notice the trip odometer and regular odometer are now both working. The only diiference I can account for is temperature.

Yesterday, it was ~72F. This am is was ~55F.

So why might it stop working?

Help!

Wed May 20, 2009 2:35 pm

Perhaps the plastic gear that mates with the worm gear is not moving with the shaft? (i.e. it is slightly cracked, and needs some adhesion of some sort?)

Cooler temps = tighter grip on the shaft :?

I just tried to fix mine as well, but it won't be back on the road for another few weeks (if I'm lucky). I glued the white gear (it was cracked) and I JB'd a stop on the other side of the shaft. when it fails (I know it will eventually) I'll follow $0.10 lead with he hard stop - great idea!

Thu May 21, 2009 5:17 am

Well it is definitely somehow heat related. As noted, it worked in the am (50 degrees), but then did not work again about mid-day (75 degrees). And now it works again this morning (60 degrees).

Any other ideas on what might be wrong besides the comment below? Would there be that much of a difference in the plastic under temperature as noted in this reply?

And why after not working yesterday, would it work for 1 mile before not working again?

I'm puzzled.

RE: Perhaps the plastic gear that mates with the worm gear is not moving with the shaft? (i.e. it is slightly cracked, and needs some adhesion of some sort?) Cooler temps = tighter grip on the shaft

Thu May 21, 2009 7:49 am

jdbs3 wrote: So I drive off this morning and notice the trip odometer and regular odometer are now both working. The only diiference I can account for is temperature.

Yesterday, it was ~72F. This am is was ~55F.

So why might it stop working?

Help!
What about the "bump" factor?

Thu May 21, 2009 7:57 am

"Bump" factor? What is that?

Thu May 21, 2009 5:32 pm

jdbs3 wrote: "Bump" factor? What is that?
When my cluster was acting up...I found that certain "bumps" in the road, potholes and driveways would switch it on and off seemingly randomly....one day "trip" then fuel, then temp.then the speedo would quit.. :(
So I took the whole cluster out, and thats when I found out. that a PO had broken the back of the speedo housing off and split the circuit film...Someone had glued the plastic back together and taped the film in place so neatly, I overlooked it. the previous time I looked at it....
I was very unfamiliar with how things should look, back then :roll:
Even though it all works now..I still have the inexplicable tach light shut off...when I hit a pothole on the passenger front wheel :?

Fri May 22, 2009 5:31 am

No, not the "bump" factor for me given the roads I was on. I'm still hoping someone else might have an idea on this since it is temperature related.

I'm just not convince that the plastic gear is gripping better when it is cooler out and then not gripping when it is hotter out. Yet it is all mechanical.

Anyone else ever seen this behavior and know what causes it?

----------------------
Well it is definitely somehow heat related. As noted, it worked in the am (50 degrees), but then did not work again about mid-day (75 degrees). And now it works again this morning (60 degrees).

Any other ideas on what might be wrong besides the comment below? Would there be that much of a difference in the plastic under temperature as noted in this reply?

And why after not working yesterday, would it work for 1 mile before not working again?

I'm puzzled.

RE: Perhaps the plastic gear that mates with the worm gear is not moving with the shaft? (i.e. it is slightly cracked, and needs some adhesion of some sort?) Cooler temps = tighter grip on the shaft

Fri May 22, 2009 6:08 pm

I've fixed about a dozen speedo gears the same way, and haven't heard of any of them failing. Added a little rough knurling to the end of the shaft with a pair of lineman's pliers, pressed the gear on over the knurling, then pinched the exposed end of the shaft with diagonal cutters and push the gear up tight against the pinch. You can't really get the gear off without grinding down where you've deformed it by pinching.... but that's sort of the idea. A good pinching and it never comes off again.

Mon Sep 07, 2009 9:22 am

Anything new on how to repair the metal gear so it won't start slipping again? Mine lasted about 3000 miles.

Tue Dec 22, 2009 8:23 pm

Using tencentlife's idea we did the following fix:

Using an erasing shield:

Cutting a small section out and drilling it:

Aligning it on the odometer:

With screws installed:

From above:

Make sure the shaft spins fairly easily otherwise there may be a problem with the green gear slipping.

Sat Jan 30, 2010 5:36 pm

When I bought my Westy last Oct the odometer didn't work. My mechanic fixed it (gear had slid off to right) and that lasted for the first gas tank on the beginning of my 4000 mile trip!!! Drove me crazy as Van was American so in mpg and I discovered that the tank was smaller than I'm used to.

When i got back I watched closely what my mechanic did. It's still working and I do want to cross check the distances using my GPS. Now I have a spare speedometer cable!!!

Sat Jul 31, 2010 10:48 am

The information here is good but I think it is incomplete. Here is where I'm stuck:

I have the unit out and can see that the odo shaft is spinning in the pot metal gear on the right hand side. I cannot see how to get this assembly apart to either knurl the shaft or to simply glue it.

I cannot imagine how to get the whole counter assembly off of the speedo shaft without damaging or dislocating the tiny brass spring or without breaking the clear plastic frame that holds all the gears.

So, if I wanted to glue the shaft to the metal gear without disassembling the whole thing, I can't figure out how to get glue to that place without gluing the shaft to the plastic housing.

Any further tips?

cheers, mordo

Sat Jul 31, 2010 10:58 am

STICKY

Sat Jul 31, 2010 11:36 am

mordeaux,
I had the same problem; I could not get the clear plastic gear carrier to come away from the base enough to work with the "small gears" (the uppermost shaft holding the numerous little gears that mesh with the master odo number gears) the number gears and their shafts. I could pull it away about 1/4" but the little brass spiral spring piece kept it from moving farther away from the black base, so what I did was then twist it a few degrees clockwise so the "small gears" shaft was aimed at the "upper left" of the four mounting posts on the black base, then I eyeballed the relative position of that gear shaft and drilled a hole so the gear shaft could be pushed out of position holding the small gears through the hole I'd drilled. That let me remove the small gears and that shaft, then have access to the master odo number gears and lightly knurl the right end of that shaft so the metal gear stays put. I probably have pix somewhere if that'll help. My repair has held for 3,000+ miles so far.

Knurling note: do NOT get too enthusiastic with the pliers. It only takes a little or you'll have to sand the shaft down to get the metal gear back on it. What some have suggested instead of knurling the shaft is to take a small Phillips screwdriver and place the tip on the hole in that metal gear and tap lightly with a hammer to, in effect, knurl the metal gear's hole instead of knurling the shaft it fits on. Same result, evidently.