Triumph TR7 Electronic ignition

[skertonman]

Morning all, looking for some help/guidance before I start banging my head against the wall.

After reading previous posts regarding Accuspark electronic ignition I took the plunge and bought the kit (no 31), and a new coil to fit to my 79 TR7, the coil came as part of the package.

All seemed to be going well, as it could be after fighting with the dizzy bolts, then comes to the wiring up, and hence my call for help.

There were 2 wires to the coil low tension side, White/Yellow and White/Slate, there was a seperate White/Slate leading from the dizzy (points) to the main engine wiring loom alongside the other 2 wires going to the coil.

Anyone know how these wires and the 2 wires from the new igniter unit all connect, I've read the workshop manual, and the fitting instructions but seem none the wiser.

The previous posts mention the new Red wire goes to the ignition switch, but I can't access the photos frpm that previous post, which is some years old.

All suggestions gratefully received.

Thanks

[dursleyman]

Need to go and check the wiring diagram but from memory the white/slate is the signal wire to the rev counter.
The white/yellow goes to the starter motor. When you operate the starter it gives a full 12 volt supply to the coil as long as the starter is engaged, instead of the usual 6 volts that it gets via the ballast in normal running.

Many electronic ignition sytems need 12 volts to operate properly so you may need to check if your new coil is a 12v or a 6v one as well.

I run my electronic ignition with a 12 volt coil so that white/yellow wire is redundant and disconnected both ends.

[Beans]

WS goes from coil to distributor and rev counter.
WY runs from starter relay to coil and ballast wire.

The module will (probably) need a 12V feed, so best to run a wire directly from the ignition switch to the ignition.

Bypassing the ballast wire and fitting a 12V coil may have some effect on starting the engine as it will get a weaker spark.
The original set up bypasses the ballast wire during starting, giving 12V on the 6V coil. This will give a bigger spark, aiding starting.

[skertonman]

Am having another play with the 7 tomorrow, anyone got any further ideas how to wire the coil up?

Seems strange to be leaving a dual wire (white/slate) left dangling from the main engine loom.

The single white slate from the neg terminal on the coil works the tacho, the car will run with a live direct to the igniter Red wire.

Have tried Emailing the Accuspark tech guy but it's a bit of a tumbleweed situation from that end.
All suggestions gratefully received.

[busheytrader]

When I converted my wedge to V8 many years ago using the S&S kit, it came with a wiring diagram on the small mods needed to accept the electronic distributor. The instructions were to leave the white / grey wire disconnected as it was no longer required so your issue sounds about right.

Everything worked fine.........although the V8 distributor itself succumbed to its usual problems (rubbish OPUS item) I replaced the innards with Lumenition Optronic which has been 100% reliable for almost 30 years and the white / grey wire is still disconnected.

Adam

[skertonman]

Adam,

thanks for the response, just seemed a little strange to leave the double wire disconnected. I will wire it up and hope for the best

Phil