PLC2 Ignition Switch

[airarms64]

Morning,my PLC2 switch has gone u/s again so not wanting the aggro of pulling it apart again can someone tell me how to bypass the ignition side as this is the u/s bit and put a separate switch in to work along side the PLC2 so i have lights and hi low charge still of the old switch the nippy is still 6 volt poss earth
Many Thanks
Simon

[GM6VXB]

You can put a switch between 'IG' and 'A' to bypass the PLC2 ignition switch.

If you push the ignition key in fairly hard and it works, then it might be worth doing my 'bodge' to
get the switch to work.
Basically it is gluing a washer over onto the switch ( Superglue GEL recommended).
It does work, but also have an ignition switch wired across 'just in case'.

Martin, GM6VXB

[Tony Griffiths]

Martin, thanks for the tip. Can you explain it in more detail - and perhaps provide some pictures?

[GM6VXB]

If the ignition is not working on your PLC2 switch is not working, but lights are, then there is a
good chance that the metal part around the ignition switch has worn and the contacts on the bottom
of the switch are not making good contact.
The easiest way to check this is to switch on the ignition and press the key firmly into the key socket.
Chances are the ignition will work, but when you let go of the key it all stops or is intermittent.

Now there are three ways (I have found) fix this:
1. fit another switch between 'IG' and 'A' on the PLC2. I already had a second switch fitted when I bought
the car.

2. take the switch apart, push the metal barrel out (using a drift or drill) so it cannot move forward out of 
the switch.
Yes this works, but it is not an easy job and you will add lots of Pounds to your swear box.

3. as per pictures, find a washer that covers the barrel of the switch, but still lets the key go into
the switch.
clean both the top of the switch and the washer, preferably with emery paper so you have good clean
surfaces.
For my switch I used Superglue GEL which is slightly easier to use than normal superglue.
Caution: do not put too much glue onto the switch, otherwise you will glue the barrel as well as the washer.

Glue and press-hold the washer onto the top of the switch until the glue has dried. You will need to press
 the washer into place against the switch internal spring. Good chance you will also glue your finger to the top
 of the washer !.

When the glue has dried, try the key and hopefully you will now have a working ignition.

For info, I have had a PLC2 switch apart (the one in the picture). Not an easy fix but using this switch as my 'standby'.
I could not be bothered to remove the switch on my tourer, hence using the washer method.
So far it is working well, but do have an old Mini switch wired across incase the PLC fails.

Martin, GM6VXB

[airarms64]

Many thanks for that i will do a switch first to get the car up and running then have a look at the washer fix
Simon

[Colin Morgan]

As those who have dismantled one of these early spade key PLC switches will know, the pressure that holds the ignition contacts together deep inside is produced using a small spring below the metal 'barrel' that the key turns. The pressure from this spring is resisted at the top by the 'keyhole' metal around where the spade key is inserted. If this breaks away completely, the 'barrel' can pop out and the spring falls loose inside the switch. Whilst the barrel can still be pushed back in place, there is then no pressure to make the electrical contact between the brass pads within the switch. Adding an external washer is a good workable solution as the 'barrel' is then held in place against the pressure of the spring and the key can be inserted as before. It may be necessary to dismantle the switch to put the spring back in place. This must be done with care as the whole thing can fly apart driven a second, larger more powerful spring inside. However, if everything is kept under control, and the orientation of the top maintained, it can be a relatively simple 'operation'. So long as this spring is in place, and everything is clean inside, there shouldn't be any need to press in the key hard to achieve a good contact.

On my car, where a screwdriver has been used for years to turn on the ignition - by others and me, there is very little metal left holding the ignition switch together - so I am very gentle with it in the hope of prolonging its useful life. Unsurprisingly, old switches in serviceable condition appear to be rare.