Classic cars forum & vehicle restoration.

[ukdave2002]

[FAB Cruiser]

Guys,

I'm back on the case trying to sort out noise with my Zephyr. I've picked up some resistive spark plugs and a capacitor to put on the alternator.

Please can someone remind me which lead the capacitor goes on? I have two terminals marked + and one terminal marked 'IND'. I have a multimeter so can check them if I know what I'm looking for.

Thanks
David

[peter scott]

Hi David,

One of the coil terminals will connect to the side terminal on the distributor.
The capacitor should be connected between the other coil terminal and the mounting bolt for the distributor.

Peter
_________________
http://www.nostalgiatech.co.uk
1939 SS Jaguar 2 1/2 litre saloon

[FAB Cruiser]

Peter,

I'm being a bit thick here. I don't understand what you mean by coil terminals and side terminals.

There are three wires to a block on the back of my distributor. Two thick wires go to two terminals labelled '+'. Then a thin wire goes to the terminal labeled 'IND'.

From the circuit diagram, I believe the thick wire goes to the voltage regulator. Not sure about the thin wire yet as it isn't on the original diagram with the dynamo and I haven't traced it.

Thanks
David

[peter scott]

Hi David,



Your car would originally have had an ignition circuit rather like the above diagram (with 6 instead of 4 plugs) but it sounds as if you may have electronic ignition fitted. Could you take a photo of the distributor showing this block mounted on the back? And maybe another showing the coil.

It would also be useful if you could remove the distributor cap and the rotor arm so that we could see the contact points. (or what ever else is in there)

Thanks,

Peter

(If someone has fitted electronic ignition it could be the root of your problems. Such systems are quite good for reducing maintenance in everyday transport but may be more trouble than they are worth in a car that is just for fun use.)
_________________
http://www.nostalgiatech.co.uk
1939 SS Jaguar 2 1/2 litre saloon

[FAB Cruiser]

Peter,

We're both getting confused. You mentioned 'distubutor' then I copied you!

If you go up to my first post this evening, you'll see this is about suppressing my Alternator with a capacitor.

My excuse this end is three cans of Badger Tanglefoot!!

Thanks
David

[peter scott]

Hi David,

I had a pint at lunch time but I guess I can't really blame that now. Must have been "senior moment".

Sorry for the confusion. Connect the capacitor between the metal case of the alternator and one of the two terminals with the thick wire connections.
It doesn't matter which you choose.

Peter

p.s. The IND (charge indicator) connection will go to your ignition warning lamp. It is possible that interference could be radiated from this connection too. So if you don't achieve a cure with the thick wire + capacitor you could try disconnecting the IND connection to see if that affects your radio interference and if so buy another capacitor to connect to the IND connection.
_________________
http://www.nostalgiatech.co.uk
1939 SS Jaguar 2 1/2 litre saloon

[FAB Cruiser]

Well I've finally cracked my problems with interference to the CD and alarm.

Switching to resistive spark plugs (NGK BR6ES) did the trick.
I also suppressed the Alternator with the capacitor but that alone didn't make much difference.

The spurious voltage coming out of the alarm controller to the siren dropped from nearly 4V to 0.1V and putting the unit in a metal box seems to have dropped it to zero.

Thanks for all the tips guys.

Cheers
David

[peter scott]

Excellent! The plugs are a nice fix. It's just a pity the alarm designer gave you so much grief.

Peter.
_________________
http://www.nostalgiatech.co.uk
1939 SS Jaguar 2 1/2 litre saloon