The 'E' Type Forum

Hi, I have a UK 1973 V12, when I turn the ignition on the rev counter needle goes right round the gauge. Any suggestions?

Thanks!

Hi Alan
Mine does exactly the same not ideal I know, BUT i made some enquieries on the subject and to have it tested and recond ?70 if
you need his number I have it

Thanks Dave C

73 SERIES 3 WHITE ROADSTER

Thanks Dave

I think the problem may be wiring related. When I turn the key to the first position the rev counter moves approx. 1/3 of the way around the gauge, if I turn the heater fan on in instantly moves all the way round. I'm going to have a look at my workshop manual and check all the earth connections. I will report back if I get any success.

Cheers

Edward.

Thats good I have had a poke around and could not sort it so if you have any luck that would be good

Regards Dave C

The S3 tach is driven from the OPUS ignition system so make sure a previous owner has not connected it to the coil! It connects to the OPUS with a blue/white wire (I think) so check the plug is OK and making good contact although that usually causes a problem of the tach not working or being intermittent. The fault could also lie with the internal circuit of the OPUS or the tach itself. Unfortunately substitution with good known working parts is usually the only way to sort it.

This site might help: http://www.reopus.co.uk/Original%20Wiring%20XJ12.html

mine intermittently does the same I have replaced the ballast and had the head checked I have as far as possible checked the live and neutral feed to the head with no improvement the next and only course of action left is the opus system itself
John

I have had my series 3 for 27 years and it has always done it - turn on the ignition and the tach moves around to 7000rpm and then settles back to zero rpm - the tach runs as it should once the engine is running.

I have just put it down as a quirk nothing more.

Garry