Resistor wire to coil

GWEN1974

New Member
Hi, I'm tracing wires to the coil on my 1974 3500 Auto before I fit electronic ignition.
I have the two white/black wires to the distributor and tach on one side of the coil and two white/yellow wires (one thicker than the other) on the other side which I assume are the feed from the starter solenoid and the resistor wire.
6" from the coil, the thinner wire is connected to a pink/white wire which I am assuming is the resistor wire. Before I start unravelling the loom and cutting wires to replace the resistor wire with a new length of standard wire, is my assumption correct?
The workshop manual wiring diagram (ref 2RA309A on bottom left of the diagram) shows a resistor with a white wire in from fuse position 19 and a white/yellow wire to the coil.
Thanks
KJ
 
Why would you cut anything and not just run another wire? Best use heatshrink on the end to isolate and leave be so in principle it can be reversed.
 
Dont assume anything! Check voltage at the coil input (with ign on of course). Mine is also a 74, and I have 12v at the coil, and have the correct coil for 12V input, IIRC a Lucas DLB101, 3 ohm.
 
on the ignition coil plus terminal, I have two white and yellow wires, negative terminal, one black to distributer.
there is two wires fixed together, black and white hanging loose. a further two wires black and white, crimped together, hanging, any ideas
car starts and runs, tacho working
thank you
 
on the ignition coil plus terminal, I have two white and yellow wires, negative terminal, one black to distributer.
there is two wires fixed together, black and white hanging loose. a further two wires black and white, crimped together, hanging, any ideas
car starts and runs, tacho working
thank you
One is the ballast one is to the starter to give you 12V. So disconnect one wire and start the car. If it starts then stops when you stop turning the starter, the you know the disconnected wire is the ballast. And vice versa if the car starts and runs.
 
One is the ballast one is to the starter to give you 12V. So disconnect one wire and start the car. If it starts then stops when you stop turning the starter, the you know the disconnected wire is the ballast. And vice versa if the car starts and runs.

thanks for that, my problems are, the wires hanging??
 
Most likely one is a spare switched 12v wire for things like Icelert. Other(s) could be the fog light wire connected to the fog terminal on the light switch (it's down there somewhere) or the washer bottle pump. The last page of the owners instruction manual should have a diagram specific to your car's wiring. Look for the pickup points on it and match the colours.
 
Thanks Mike
My problem is, I do not have the owners manual, (any out there for sale) I have got a Haynes (spelt wrong) one, NMG, (not much good) wiring diagram colour codes unreadable, I am pretty sure one of the pair was on the coil, that was before I got a classic car tune up? person to do the timing, said the engine kept seizing up when hot, until he found the car was out of fuel, (petrol gauge not working) so £289?? light. I have two wires adrift, that wasn't before.
I have come to the conclusion now about this car, one step forward three steps back.
My grandad who I did not like, who is now about 200 years old is haunting my garage and the car, answers on foolscap? please
Regards
Brian
 
Ah... Well the spare wire will have 12v when ignition on. The 12v starting wire will only give twelve volts with the key in the starting position against the spring. The ign ballast wire will read less than 12v (around 7 ) with ignition on. Fog lights. washer pump (two wires one black) etc will only show voltage when that wire's switch is on. There should be two wires going into the coil terminal and one coming out on the opposite side which will go across to the distributor.
 
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