[T3] '72 Type 3 Progress

[Jim Adney]

On 18 Jan 2012 at 23:05, Jeremy Menzies wrote:

> Speaking of the speedo your working on, I pulled mine (from a '71 sb)
> to check out why the odometer was working intermittently and
> discovered the shaft (possibly 'input'?) connecting the 'main' gears
> at the bottom to the odometer digits had a small brass gear that is
> badly worn.  The whole shaft has a spiral gear on the end linked to
> the digits and the aforementioned standard-looking brass gear linked
> to where the cable connects up.  The teeth on the brass gear have worn
> into fine little points so much that the teeth of the other gear slip
> right off, causing a few miles to log for every many miles driven. 
> Does anyone know if these shafts are the same on regular (no trip
> digits) and 'trip' odometers?  I imagine the extra distance required
> for the 'trip' section makes them different but I've never seen the
> insides of any others. 

There really are no common parts in the gear trains of odometers of 
different styles. Does your '71 speedo have the trip odometer, as US 
code ones have? If so, this sounds odd, because I THINK the gear that 
you're describing should be running against a nylon worm gear, and I 
never see that kind of wear on gears that run against nylon gears.

OTOH, there are lots of variations in VDO speedos, and I may not be 
remembering the '71s correctly. 

I MIGHT have a part I could salvage from a broken speedo that would 
be right for you, but I'd also want to do the whole job, which would 
cost $50 plus $10 for that gear/shaft and return shipping. If you 
took a photo for me, I could check to see if I have the right part.

Like the other guys, I'd want to do the whole job, because there are 
several pitfalls and I really wouldn't want you to get caught in one.

> I'm thinking if they're the same I'll try to pick up a used parts
> gauge and steal the shaft.  Otherwise, I'll have to see if my
> machinist friend could fabricate me the worn gear.  There is a place
> near me that rebuilds VDO gauges but I imagine they'd want to do all
> the work and charge me an arm and a leg for it all... 

Finding another identical speedo is probably the best option, but 
that will be hard, since that'a a one year only item.

> Good luck with that rusty distributor, sounds like a big mess. 

Yeah, everything else turned out well, but I'm afraid that's just not 
going to make it. I bead blasted the rust off the ignition cam, but 
the rust left huge pits in it that I think really pushes it over the 
edge. Oh, and the vacuum adv/ret can is bad....   ;-p

Sorry, Dennis. Now you get to think about your backup plan....

-- 
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Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
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