MGB Register Forum

Hi there can anyone assist, on starting my BGT 77 Model the Rev Counter doesn't,t operate but after a few minutes it works normally any suggestions appreciated.

Has it been like this for a while or did it start following some recent work on the car ?

There,s been no work on the car only engine tune up

Different ignition system fitted? Tachometers work on ignition pulses.

Ian F

I always have to tap the glass to get my rev counter working. Have done so for years.

Thanks for your input will try your suggestions

Probably not provided much for you to go on Tom. Intermittent faults like this are always tricky. I suggest checking all the wiring connections. If it is just a sticky needle in the instrument you could look inside, but perhaps best left to a specialist to overhaul the unit.
Speedograph Richfield have done similar overhauls of instruments for me.

Ian F

Thanks Ian,have sent the Unit for repair to instrument tech.

I always have had to tap the glass too. Needle stop perhaps magnetic?

Hi all, have a look at this site....
Tach issue with switch to electronic ignition : MGB & GT Forumhttps://www.mgexp.com › forum › tach-issue-with-swit.