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Rev Counter

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M

mgbcca

Freshman Member
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I have a '75 MGB. I have put it away for a few months until the spring, but I fired it up the other day and noticed a problem with the rev counter.

The counter is reading very low. It indicates up to about 1500 rpm and the needle moves in response to the engine revs - just much lower than they really are.

Any suggestions before I start crawling under the dashboard?

It also looks as though there might be some condensation in the rev counter (and other instruments).

Thanks for the help.
 
Since the tach is reading revs, it is probably in the 12V supply. The first place I would check is the fuse box. I have fixed a lot of voltage problems by just rotating the fuses to clean them.
Next, I would get the wireing diagram out and check along the 12V line to see if you are getting the right voltage with a volt meter. There is a regulator and I believe it drops it to 10V. I don't remember for sure and my diagram is in the garage.
My gauges get fogged up a lot but this doesn't seem to affect the readings.
Bob
 
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