TR2/3/3A TR3 Speedo Part Needed

[Moseso]

As if things weren't funky enough with my car lately, the little shaft in the speedo holding the little 20 tooth fiber gear that operates the trip odometer froze in it's bore -- stripping a tooth off the gear and breaking the speedo cable.

I was smart enough to check the input shaft on the speedo before just plugging the new cable into it. And, when it didn't turn, I took it apart. Though clearly, not smart enough to have taken it apart, to find out what was making my speedo bounce, before an unobtainium part was destroyed.

So --
Does anyone here have a funky 1180 turns/mile parts speedo s/he would part with -- or better still, just the little shaft with the eccentric pin on one end and the little 20 tooth fiber gear on the other?

 

[TR3driver]

I'll have to check if it's 1180 or not; but I might have just what you need. Bought a parts car once, and the neighborhood kids decided it would be fun to climb into it (still on the trailer) and bash the gauges with rocks.

 

[martx-5]

That's a VERY COMMON problem with the TR3 speedos. The shaft that holds the fiber gear runs directly in the aluminium housing and is lubed with a heavy grease that turns to paste over time. This locks the shaft in the bore, stripping those delicate fiber gears.

I made a gear for mine starting out with a McMaster item dimensionally close to the original.

I explained what I did in this thread.

BTW, the odometer is still working fine...(where's that piece of wood to knock on!) :laugh:

 

[Moseso]

Thanks for the link, Art!
That looks like the kind of thing I do. I just didn't know where I might find a proper gear. You posted in April '07, and it's still working That sounds good enough for me!

I'm going to lube up the shaft on the odometer gear too...

Going surfing now. See if I can find a closer fit than you did.

 

[martx-5]

Well, in all honesty, I didn't get the car completed until earlier this year, so there are only about 1500 miles on that odo gear. But it has run this long, so I suspect it will go for quite awhile longer.

I also used just a drop or two of oil on the shaft and bore. Hopefully that won't turn to glue over time. :eeek:

 

[Moseso]

So, I found a place called Stock Drive Products/Sterling Instrument. No minimum, order if you order on-line. They have a .125" x .460" OD - 20 tooth nylon gear that looks like a possibly easier mod than Art's. At least, it doesn't have a hub that needs to be cut off. The bore still needs to be expanded from the stock .125" size, to fit the odometer cam shaft.

If I need to deepen the gullets on the wheel Like Art did, I have some nifty tools for that. In the guitar business, we need to shape "nuts" for guitars. The nut is the piece at the head end of the neck that has six little slots in it to hold the guitar strings. The strings are different sizes, so the slots need to be, as well. I have a whole set of files, that cut only on the half-round edge of the file, in sizes from .010" to .125". One of those should be just the trick to adjust those gears, if need be.

More news after the gears arrive.

 

[martx-5]

Sounds like a plan Moses...

It's takes a certain kind of kook to spend $3 on a part, an hour to get it to fit, or maybe more if the first one doesn't work out, re-assemble the speedo and hope it works...when it does, the feeling of accomplishment over such a minor thing is wonderful! The restoration of my TR3 had many moments like this.

BTW, I'm good friends with a luthier by the name of Pat Caruso. He has built a baroque guitar and arch lute for Jerry Willard one of the great classical guitatists around. The two instruments on the first page of Willard's site are Pat's instruments. Pat wanted to start building guitars many years ago, we (I say we, because I wanted to try it also) got going in my basement only because I had a lot of wood working tools. Pat went on to greatness, and I only wound up building two instruments. It's an art that I admire.

 

[Moseso]

Fortunately, I am just that sort of kook; which is probably why I repair guitars for a living, and tore a TR3 down to the ground and put it back together. There are more like us here too.

I actually <span style="font-style: italic">hate</span> it when some $50 assembly goes south because of a genuine $0.49 part, that isn't that hard to replace -- and the manufacturer doesn't make the part available. While I can understand that it might not make sense for most people, who would pay a mechanic $85/hr to rebuild the part, LOTS of other people (like me) would rather do it themselves, and NOT buy a whole new unit.

This speedo fix isn't that hard. Parts availability for 50-year-old cars is spotty -- and I don't expect someone to be selling Jaeger odometer gears -- even though there seems to be a rash of failures due to their extreme age. It's cool to find a generic part that will do the job, and make the odometer run for another 200,000 miles.

Thanks again, for the prod in that direction.