tachometer not working

Hello, My 1982 300 TD tachometer works occassionally. Would welcome suggestions on how I could get it working all the time again. 236,000
miles and still runs like a champ. Thanks!! Bob
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.