Rev counter

Technical MGB discussion
TomMGBGT
Posts: 5
Joined: Tue Jan 19, 2021 6:38 pm
Forename: Thomas
Surname: Roach

Rev counter

Post by TomMGBGT »

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.
Not_Anumber
Posts: 101
Joined: Tue Sep 22, 2020 9:33 am
Forename: Chris
Surname: Silk

Re: Rev counter

Post by Not_Anumber »

Has it been like this for a while or did it start following some recent work on the car ?
TomMGBGT
Posts: 5
Joined: Tue Jan 19, 2021 6:38 pm
Forename: Thomas
Surname: Roach

Re: Rev counter

Post by TomMGBGT »

There,s been no work on the car only engine tune up
Ian Fozzard
Posts: 655
Joined: Fri Mar 27, 2015 8:18 am
Forename: Ian
Surname: Fozzard

Re: Rev counter

Post by Ian Fozzard »

Different ignition system fitted? Tachometers work on ignition pulses.

Ian F
1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, Clipper Blue, Blue trim and weather gear
Vic Butler
Posts: 620
Joined: Wed Dec 21, 2016 6:07 pm
Forename: Vic
Surname: Butler
Location: North West Hampshire

Re: Rev counter

Post by Vic Butler »

I always have to tap the glass to get my rev counter working. Have done so for years.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
TomMGBGT
Posts: 5
Joined: Tue Jan 19, 2021 6:38 pm
Forename: Thomas
Surname: Roach

Re: Rev counter

Post by TomMGBGT »

Thanks for your input will try your suggestions
Ian Fozzard
Posts: 655
Joined: Fri Mar 27, 2015 8:18 am
Forename: Ian
Surname: Fozzard

Re: Rev counter

Post by Ian Fozzard »

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
1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, Clipper Blue, Blue trim and weather gear
TomMGBGT
Posts: 5
Joined: Tue Jan 19, 2021 6:38 pm
Forename: Thomas
Surname: Roach

Re: Rev counter

Post by TomMGBGT »

Thanks Ian,have sent the Unit for repair to instrument tech.
JohnH
Posts: 10
Joined: Wed Apr 03, 2019 11:12 am
Forename: John
Surname: Howard

Re: Rev counter

Post by JohnH »

I always have had to tap the glass too. Needle stop perhaps magnetic?
Sean Lynam
Posts: 3
Joined: Fri Oct 31, 2014 4:01 pm
Forename: SEAN
Surname: LYNAM

Re: Rev counter

Post by Sean Lynam »

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.
Post Reply