Coil And Distributor Wiring

[chrishewett]

I am just fitting a new distributor with aldon ignitor electronic ignition and a flamethrower coil. I have got two wires to the positive side of the coil, one from the starter solenoid and one comes out of the wiring loom. When I fit the new dizzy I have got one wire for the negative side of the coil and another for the positive side. As you may have noticed I have already got two wires going to the positive side. I may be being very thick but I dont have three terminals on the positive side. The manual is not very helpful and autoelectrics is not my strong point (as you may have noticed).
Can anyone help?
Chris

[types26/36]

Chris,
Sounds like you had a ballast resistor and coil fitted as you mention a wire to the starter, you proberably do not need the starter wire with your new coil if you have a full 12v supply to the new coil, I am not familiar with the Aldron or Flamethrower coil so dont know. It may be of help if you mentioned which Elan you have and the colour of the wires.
Brian

[tdafforn]

Hi,
Just in the same position. Elan +2s130 and an aldon.
Also had 2 wires going to the +ve pole on the coil.
First checked which of the two gave voltage with the ignition on (one gave 12v the other nothing.)
Disconnected the one without voltage and replaced it with the Aldon wire.
The car started fine.
Then chatted to some people and they mentioned the fact the other wire is part of the ballast resistor circuit the provides a higher voltage to the coil during starting.
So have now replaced the wire and have talken a 12v ignition switched feed from the brake light switch (under the master cylinder). I haven't tried this yet (will try tomorrow) but I am hoping it'll give the best solution.
Let me knwo how you get on
Cheers
Tim

[tdafforn]

Hi,
Checked the car this morning with the new wiring and it starts and runs fine
Cheers
Tim

[mark030358]

Just a quick question, do you earth the body of the coil? If I remember the "flamethrower" and the "gold" coils appear to be insulated.

cheers Mark

[types26/36]

That question has been discussed on mailing lists before with some people insisting the body has to be grounded and others say not.
I have never been able to understand why it should be, as an apprentice in the motor trade many years ago we had at the traning centre a coil which had a glass body, this was for demonstration and it was used to run an engine so thus no ground.
Recently on ebay there was a glass coil and although I didn't bit for it I think I saved the picture.
Brian

[rgh0]

The ignition coil consists of 2 windings acting as a transformer to produce the high voltage spark. Both windings have 2 ends of wire that need to go somewhere to complete a circuit otherwise no current flows

The low voltage coil is connected between the 12 V supply and earthed via the points or electronic ignition system.

The high voltage coil is connect to the spark plug at one end and to what at the other ? Two options

1. It can be connect to the low voltage coil at some point ( does not mater if at 12 volt end, earth end or somewhere in between

or

2. Can be earthed via the can of the coil.

All of these points are effectively earth compared to the 20,000 plus volts generated in the high voltage windingl by the collapse of the magnetic field in the primary low voltage coil when the points open. You just need a location for the electrons forming the spark to go to and from in the high voltage winding side of the ignition coil. A glass bodied ignition coil would have used the low voltage side as the non spark plug end of the high voltage coil winding.

Improperly earthed coils or coils that use the low voltage winding as earth for the high voltage winding are one of the many reasons for problems with boucing or miss reading tachs in Lotus or poor spark performance.

Easy enough to test a coil for how the high voltage winding is earthed with a multimeter. I always use coils with the high voltage winding earthed to the body of the coil and ensure the body is properly earthed to the chassis.


regards
Rohan

[type26owner]

Maybe these two links will help. The Ignitor is made to handle the full battery voltage. That voltage actually is nearly 15 volts when the charging system is engaged. Leaving the ballast resistor installed is not recommended but it probably will run okay. May develop a misfire at WOT at high rpms though.
<a href='http://www.vtr.org/maintain/ballast.shtml' target='_blank'>http://www.vtr.org/maintain/ballast.shtml</a>
<a href='http://www.lotuselan.net/publish/lsb_cold_start_coil.shtml' target='_blank'>http://www.lotuselan.net/publish/lsb_cold_...tart_coil.shtml</a>

The Triumph article goes on to tout opening up the plug gaps. Horsefeathers! Only necessary to do this if you've got a misfire due to excessive cylinder pressures at WOT at high rpms. Tune your engine correctly and it will start first time, everytime.

[tdafforn]

So the balast resistor is a projection on the top of the coil onto which the separate feed connects?
I have 2 wires going to the +ve side of the coil, and no sign of the ballast resistor, is this wrong?
Cheers
Tim

[type26owner]

Tim,
Can't tell you for sure since I've never seen the ballast resistor setup on an Elan before. It can be a wire or a connector looking device bolted to the coil. The Lotus Service Bulletin hints it's a connector type. In any case the wire leading from the starter solenoid is redundant and can be removed as Brian stated earlier. The white wire from the wiring loom should have the voltage measured with a VOM to make sure it's delivering full battery voltage.

The Ignitor will work just fine with 9 volts powering the gate (red wire on a negative earthed car). IIRC, the Pertronix engineer stated 6 volts is okay too but shouldn't drop any lower then that. I use a 9 volt dry cell battery to power the gate when I'm testing a dizzy on my Sun tester. If you live in really cold weather then perhaps leaving a ballast resistor and lower voltage coil in the ignition system is the smart thing to do. This will help makeup for the loss of cranking power from a battery that is down on power from being chilled. Just limit the current which follows through the primary circuit to 5 amps or below and this solid-state device is pretty much bullet-proof.

[types26/36]

To follow on to what Kieth was saying, I also have never looked at a ballast resistor on an Elan but my Europa is fitted with one and that is a round block about 1/2" in diameter, attached to the coil terminal. You cannot miss it if it is there.
Brian