Hi I have a Jaguar XJS 1988 V12 I am unable to get a spark at the plugs, I have a doner car and have used parts to rigg up a full bench mounted system ie distributor with new electronic proximity sensor (that is grounded to negative), 2 coils wired in parallel with HT lead to the spark plug (grounded to negative), an amplifier with new GM unit and HT lead connected to the positive and negative of coil 1, on rotating the distributor drive past the pick up I cannot produce a spark.
I have wired an old MGB points distributor in the same way removing the amplifier and get a great spark.
I am obviously doing somthing wrong but not sure what?
I want to prove the system on the bench then transfer my knowlage to the car, but I am currently at a loss.
Anyone had the same issue ??
any help greatfully recieved

 

Folloeing you somehat, but thats all.

NO spark on a Lucas HE is known to be:
1) Noise suppressor Condensor inside the AB14 amp, remove it, the dog needs a new toy. They leak to earth, NO spark.
2) Carbon brush inside the cap has fallen out, gravity is an aswesome thng.
3) The wires from the dizzy, through the rubber grommet in the lower corner, break inside that grommet. Ohm test the continuity, and wiggle the wires around.

Your on the bench so I will assume good earths. the engine earth strap fiasco is fickle on any day.

I would use ONE coil for testing, as the 2nd, out the fron, really does little to xero until 3000RPM is reached.

 

I suggest you check the wires from the dizzy base to the amp for continuity. The amp is not receiving the signal.

 

Hello, Please help a Yankee in the U.S. with terminology. What is the "Dizzy"? Is it the aluminum base of the distributor?
Thanks Al in Michigan

 

Aussie speak for distributor, and way shorter to type.

 

Thank you for the reply. Attached is the start of my Speedster/Sportscar build. Will be test firing engine in the chassis soon. Will be fun set up wiring to the Dizzy!