Thursday, February 16, 2012

The Recalcitrant Vanagon Odometer

Odometer failure is a problem common to Vanagons.  If both the speedometer and the odometer are unresponsive or operating erratically, check the drive cable first.  As with Volkswagens of old, this cable runs from the left front hub grease cap up through the the body, under the dash, and fastens to the rear of the speedometer.  This is a relatively inexpensive part and easy to replace.

If the speedometer is working, but not the odometer, it usually means a tiny plastic gear inside has cracked or moved on the shaft so it's no longer making proper contact, or maybe both.  Important!  Collective internet wisdom says the quickest way to render the Vanagon odometer inoperable it to push the trip reset button while driving.  So, be safe and push only while stopped even if the yahoos behind you at the gas station are honking for you to move out of the way so they can hurry up and get their fill or get out.

Speaking of gas stations, yesterday I was filling up and a little right hand drive car pulled up alongside.  I had never seen one before, so I queried the driver (very friendly, and in a matching outfit). This was a 1985 Honda City that she had imported from Japan.  

1985 Honda City Cabriolet.  The white van in the background later honked at me
when I stopped to reset my trip odometer
Very fuel efficient with a 1200cc engine and transmission with overdrive in 2,3 and 4th gears giving it a range of 7 speeds.  The cabriolet (convertible) body was designed by Italian coachbuilder Pininfarina.  

Choice of red, white or blue
[Photo courtesy of thepetrolstop.com]
An interesting option was this 50cc motorbike. Stuck in extra heavy Tokyo traffic?   Just whip this out of the back and get on your way.  

Anyway, back to the task at hand.  Westly's odometer had been unresponsive through his past couple of owners and I decided it was time it was ticking off the miles again.  I removed the instrument cluster by carefully (30 year old plastic gets brittle) releasing the tabs on the back of the cover and pulling up (Surprise! - The brake and clutch fluid reservoir is under there!  And a tip - a little dab of grease on the metal tabs makes removal and replacement of the cover much easier).  Four screws hold the cluster onto the dash.  Careful with the switches and electrical connector on the back.  Once it's out, a flexible blue foil circuit board must be removed, then the speedometer can come out.  Upon inspection I found the suspect gear to be about 5mm from the corresponding worm drive that it needs to snuggle up to for proper operation.  I pushed it back over and added a drop of epoxy to the shaft to hold it in place.  This innovative fix held for about 1.5 miles.  I removed it again and upon closer inspection I found the gear had a crack halfway through. "A little super glue ought to hold this" I thought, erroneously, to myself as that fix lasted only about 10 miles.

I Googled "vanagon odometer fix" and found several schemes involving brass collars, circlips, JB Weld, vice grips, etc.  Odometergears.com sells a replacement gear for $25. Or I could send it to Van Cafe (see my list of favorite links), properly packaged so it would not be crushed in the mail and for $58 they would return it in working condition.  I decided to try fixing it myself, figuring that if I somehow destroyed it (entirely within the realm of possibility) I could always buy a new gear.

I removed the gear and carefully (didn't want it to split entirely in two) pried the crack apart.  After dousing with isopropyl (rubbing) alcohol to clean the grease off, I filled the crack with super glue then used a pair of locking forceps to clamp it.  While the glue was setting up, I found two 1/4" external circlips and removed the "ears".  I then pried open the circlips (the circlip tool cannot be used because the ears are now gone) and forced them over the collars surrounding the gear on both sides.  The circlip has just enough inward spring (fingers crossed) that they, along with the super glue, will keep the gear collar secure.  Sorry I didn't think to take a picture of any of this, but if you are going to try it yourself it's all pretty plain to see when you are looking at it.
External Circlip
Snip off the two ears (larger area at the top with the holes in the middle)
Before replacing the gear, I used vice-grip pliers to add a little knurl (some roughage) on the shaft to keep the gear from wandering away again.  I lubed the other gears and shafts sparingly with powdered teflon and put it all back together.  It worked, and has continued to do so for close to 4,000 miles now.

Time will tell - I'll keep you informed.

05/13  Update - Working perfectly 15,000 miles later!














2 comments:

  1. It's a nice informative blog about The Recalcitrant Vanagon Odometer.Glad you had such a good time.


    Speedo Repair

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  2. If you grind the circling ears off with an inward bevel u can use small regular snap ring pliers to install circlips. BTW great fix!!!

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