123 ignition system

[stevex75]

I,ve got a 1963 series 1 3.8 fhc which is nearly finished after 9 years (don,t ask) and I,ve fitted a 123 distributer with a lucas sports coil but I can,t get the car to run (no spark). Has anybody else fitted one of these successfully?
All the paperwork that comes with the 123 states that it is for neg earth only but there is one small diagram showing positive earth which 3.8,s are. I,ve followed the diagram exactly but no joy. Am I missing something obvious? Anyone got any ideas?

[daverawle]

I,ve got a 1963 series 1 3.8 fhc which is nearly finished after 9 years (don,t ask) and I,ve fitted a 123 distributer with a lucas sports coil but I can,t get the car to run (no spark). Has anybody else fitted one of these successfully?
All the paperwork that comes with the 123 states that it is for neg earth only but there is one small diagram showing positive earth which 3.8,s are. I,ve followed the diagram exactly but no joy. Am I missing something obvious? Anyone got any ideas?

Which 123 version do you have Steve? The 6-R-V (Jag or GB) version I had was negative earth only so unless something has changed it won't work on positive earth. The 123\Tune works on either polarity and with a USB port it can be curved as you like.

After some experimentation I have arrived at a usable 3.8 curve which you are welcome to.

Dave

[stevex75]

the 123 distributer I have is the "gb6rv" but there was a diagram inside showing how to wire for positive earth and on the packet it had a sticker stating positive earth

[mgcjag]

Hi Steve........Theres a forum for 123 users if you search the net.....I have one fitted to my MGC........The 123 is quite different in that you must have the plugs connected to check for a spark failure to do this can damage the unit.......also the electronics cut off the cct to the coil if the unit is not rotating to prevent the coil overheating......assuming youve wired it as per the diagram & have piston 6 comming up on compression set static to 10btdc & rotate 123 holding back rotor until led just lights......most of the probs with 123 on the forum seam to end up with faulty coil or leads...........then comes what curve to use......feal free to call me on 0797 495 2877 if needed...Steve