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tachometer repair

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Dave Russell

Dave Russell

Yoda - R.I.P
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Hi Glen,
Welcome to the forums.

The tap could be correcting a loose electrical connection inside the tach or it could be correcting a mechanical problem with the needle. Go here to get an idea;
https://www.mgcars.org.uk/electrical/body_tach.html

I don't know your skill level with precision instruments. Here are a couple of places that can repair it for you.
https://www.nisonger.com/

Moma New Mexico, Margaret Lucas
momanm@aol.com

Good luck,
D
 
Thanks for the replies guys. Dave, that page really goes into detail (beyond my expertise to understand really). I get the impression that they didn't put a lot of emphasis on quality control, especially in the description of the later tachs (changes were made to make it cheaper to build, not make it better LOL)

Carl, it bugs me a little, but I would't spend a great deal of $$ to fix it. While it may be "common" I don't think its "normal." However, I may try a can if compressed air to see if maybe it just needs to get the dust out. I'll also clean and check my connections. Nisongers looks interesting - I wonder what they would charge for a rebuild or cleaning (whichever is needed)?

Thanks again,

Glen
patriot.gif
 
Hi everyone,
New to the forum and have a 1978 MGB. Glad to be aboard. I have a question I hope someone can help with right off the bat. My tachometer gets "stuck" when I first start my car. I have to tap on it a few times then it will finally start working. Is this likely just needing cleaning? If so, is it something I could do myself without danger of destroying my tach? Or, if I should leave this to the pros, are there any recommendation of who could do this for me?

Thanks
 
Tach's and speedo's are like very small electric motors. The needle shaft turns in a bushing and after 25 years the lube dries and the shaft sticks.If you can open the housing and take out the unit, put a SMALL drop of 3in1 or sewing machine oil on the end of a pin and touch it to the needle shaft where it goes into the gauge face. Should make a difference.
 
This may (or may not) help with your tach problem: my Triumph had a very jerky Smiths speedometer needle until I installed a new speedo cable. I then "calibrated" it with a 2003 Ford following behind me to check various speeds-- it's right on the money and no more wavering, which isn't bad for a 33 year old speedo.

Replacing the cable is easy and inexpensive so if it doesn't help, you haven't lost much.

Hope this is helpful, good luck!
 
Carl is right on there. 77-80s have different issues than the earlier tachs. I've always wondered if something in there needed a little more charge to get it going, like charging a capacitor. My latest 79 needs a boost at start-up, but then is very consistent.
 
Glen -- FYI, I had my tach rebuilt by Nisonger two years ago, and it cost $100. Not cheap! But they do fantastic work -- they take it apart, clean it, paint it, and make it like new. My tach wasn't working at all, though. Was it essential to get it fixed? Nah, of course not. But it was one of those things that bugged me, and became a "might as well" when I took my dash out.
 
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