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TR2/3/3A Tach and Speedo acting up.

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mt10flyer

mt10flyer

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My tach makes an interesting friction noise and the speedo is way off (sometimes I am going 25mph at a stop sign and 40mph on the freeway, though somehow keeping up with the 70mph traffic).

Is this a project to undertake or should I ship them off to someone, somewhere for a build and if so, where?

Thanks.
David
 
Like so many other things, you can go either way. There is a good article at
https://home.comcast.net/~rhodes/PDF/speedo.pdf
that will give you some idea what is involved (although the details may vary, depending on what car you have). It is possible that all the tach needs is to clean and lubricate the bushing that carries the input; while the speedo sounds like something is rubbing inside. In my case, the gasket under the light shield ring had shrunk and turned inward until it was causing problems.

Or there are lots of places around that will do it for you. Here's a few (in alpha order):
MO-MA
1321 2nd St NW
Albuquerque, NM 87102
(505) 766-6661
momanm@aol.com

North Hollywood Speedometer & Clock Co.
6111 Lankershim Blvd.
North Hollywood, CA 91606
Phone 818-761-5136
Fax 818-761-4857
https://www.nhspeedometer.com/

West Valley Instruments
Toll Free: (877) 818-9402
19314 Vanowen Street
Reseda, CA 91335
Tel: (818) 758-9500
Fax: (818) 758-9504
westvalleyinstruments@gmail.com
https://westvalleyinstruments.com/
 
Also there's Palo Alto Speedometer Tel 650-323-0243 and one in San Diego, all in California I am reseaching this too! Keep us posted on what you find out, all seem to be quite capable.
 
If i were to clean my speedometer, how much disassembly would be required? Also what would be a good solvent or cleaning agent to use?
 
I cleaned mine with alcohol as I didn't want a residue of anything left behind. Be careful of the numbers on the odo (esp if they are the version where the numbers looked embossed & painted -- those can easily wash off. Fortunately, they were fairly easy to repaint but had to disassemble further than originally planned to do that.
 
On mine, the white paint on the face was also _very_ fragile. Later cars are apparently better in that regard. The best method I found was to not get the white letters and marks wet at all (even water was taking off the paint). Instead I used an artist's brush to lightly brush the entire face dry, then dampened it to clean the background up to the edge of the letters. Last time around, I used Pledge as the solvent, hoping it might help keep it cleaner longer in service.

To do just the face, you can just remove the bezel and glass. But at the least, I'd want to remove the mechanism and paint the inside of the housing. It lights up a lot better at night with a fresh coat of white paint in there. To effectively clean and lube the mechanism, though, requires a fair amount of disassembly. With care, you can leave the mainspring attached at both ends, but I wound up disassembling pretty much everything else. Here's a few shots I took:
https://s258.photobucket.com/user/TR3driver/library/Speedometer repair

Be careful when you remove the needle; I've managed to break a shaft just pulling on it. A twisting motion (while holding the aluminum cup so the shaft can't turn) may be the best way, but I've had good luck using a pair of screwdrivers, one under each side, then twisting the screwdrivers to apply upwards force on the metal hub (not on the flimsy metal that forms the visible part of the needle). Fortunately I've got several spares for parts (which is where that rusty case in some of the photos came from).

And as I think Tony mentioned in the article I linked to above; you will probably need to replace the rubber seals around the glass. I unfortunately forgot to document the sizes, but found some O-ring stock that I was able to cut and glue to the right size. I also put an O-ring under the outer ring that deflects the light (and painted the back of it white).
 
Well I bit the bullet and sent all my gauges to West Valley Instruments. They quoted 6 weeks and delivered them in 6 weeks. They repainted all the dials, replaced the glass and bezels and of course re worked all of them and I have to say they look like brand new. It was really the highest level of craftsmanship. They did a super job in every respect, a little expensive at $1260 for everything but worth it IMO. I'll post a pic or two in a couple of days. I am installing a new wiring harness and the dash is out right now.
 
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