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TR6 74 TR6 Speedo & Tach

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ScottTR6

ScottTR6

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I'm planning to replace my dash this winter, while I've got things apart it's time to repair both my Tach & Speedo, which haven't worked properly for years. Both tend to "bounce" constantly, or if they do settle down, read very high. The needle on my Speedo broke off, and needs repairing or replacing. Anyone know of the best place to have this done, or what it might cost? I'm in the southern Ontario area. /ubbthreads/images/graemlins/canpatriot.GIF Thanks, Andrew.
 
Hi Scott,
Alot of spedo & tach bounce comes from worn or binding cables. Before you invest in refurbashing the gauges lubricate or replace worn cables. A binding cable recoils like a spring causing an unsteady & fluctuating rpm to the gauge.
Remember that these gauges will always have some bounce to them.
 
Yep, those cables can create a lot of bounce. My tach is bouncing like crazy right now, both from the cable being kinked in a few places as well as being old and worn and needing a lube. I can actually hear it spinning and binding, makes a weird scuffing noise.

Nisonger is supposed to be pretty good. I haven't had any of my gauges rebuilt there but my buddy sent out an E-type tach to them a few months ago and it came back beautiful.
 
I replaced the cable on my tach and eliminated all of the bounce. The speedo quivers slightly between 40-54 with a new cable also. Not great but certainly not a critical issue.

I too will be doing the dash this winter and wanted to clean my gages while they are out. Are there any tricks to getting them apart or special cleaners to use once the lens is off? Both for the lenses and the black and white?
 
I did all my gauges (and refinished the dash wood) when I did the rest of the interior. The gauges were a little stubborn to get apart as they put a rubber seal of some kind in between the bezel and the glass and the rest of the gauge body. Over the years this seal turns into concrete, so I had to really twist to get the bezel off, and assisted it with some very gentle prying using a very small flat blade screwdriver between the bezel and body. You can sort of twist the blade and pry up the little locking tabs on the bezel, which will release some of the pressure and allow you to more easily twist off the ring. Just go slow and be very careful, that glass can break easily. Once I got them all apart I gently cleaned some dust and whatnot off the faces, and touched up with flat black and a small model brush in a few spots where some surface rust had started to take hold. Then cleaned the glass up real well with windex. I wouldn't use any solvents on the painted gauge faces though, could take that old paint right off. This is also a good time to replace any burned out bulbs. WHen I put them back together I used a few small spots of plumbers pipe dope around the inside edge of the bezel just so that it presses tightly against the glass and body. This will keep the glass from rattling around. Now I see a guy all the time on Ebay that sells polymer O-ring sets for the Smiths gauges, if I did the job again I'd probably order those, they're cheap enough.
 
There's another thread running in this forum also talking about gauges. I'll second all of Dotanukie's comments.

That rubber seal under the chrome is a real mess. I usually spray the joint between the gauge cup and the chrome bezel with penetrating oil and let it work in over several days. I pry up the bayonet tabs on the chrome ring only the slightest bit to remove the pressure. After that, rubber kitchen grippers (like for opening stubborn jars) can help remove the bezel. Rubber strap wrenches are another handy tool for taking off the ring. Once the chrome ring is off I soak it so I can remove all the residue from that old disintegrated rubber seal.

As mentioned above the white paint on the gauge faces is very delicate and easily removed. I limit my cleaning to using a cotton swab moistened only with water. Stay away from the lettering when possible. Do not use any solvents or soaps as this will take the lettering right off an old gauge face. I use flat black model paint (Testors) and a fine detail brush to conceal minor blemishes.

Instead of plumbers putty (which can harden) as Dotanukie mentions above, I use o-ring cord stock (or small bore tubing) between the chrome bezel and the glass. There is usually a paper-like seal that goes between the inner surface of the glass and the (typically) black inner bezel just above the gauge face. I use heavy gasket paper to make replacement rings for that seal.

I think the guy on eBay is selling the "square" profile rings that go between the back side of the gauges and the dash. I never thought there was a special reason to use square rings. Maybe if you're going for a Concours restoration.
 
[ QUOTE ]
I think the guy on eBay is selling the "square" profile rings that go between the back side of the gauges and the dash.

[/ QUOTE ]

Yep, I believe you're right about the Ebay guy Doug, now that I think about it. I'll admit, the pipe dope was not the greatest idea, and I don't suggest anyone use that. It was just what I had handy at the time and wanted to get the dash back together. Where do you get your O-ring stock from? I'm assuming this is just straight lengths of o-ring material that you can cut to fit?

Here's a question, is there any way to seal these darn things tight enough so they don't fog over inside the gauge on a humid day? Or are mine doing that because I've used the stupid pipe dope and not a proper gasket?
 
Who is this Doug and where do I find him? I've searched EBay and can't come up with anything.

Paul
 
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