Tach stuck full tilt

JD1964

there is enough sticking out to grab on to
15 Year Member
Jun 28, 2013
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Maryland
After a drive earlier today in the 92 Lx I looked at the tach and it was stuck all the way clockwise. The engine was not running when I first noticed this so I’m not sure exactly when it happened. Turned the engine on and off a few times and it still stayed stuck. Decided to drive home and fiddle with it later. After about two minutes of driving, it popped itself back to normal operation and worked probably all the way home.

What would make it randomly stick wide open then correct itself like this?
 
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