Alfa Romeo Owners Club of Australia Forum

Technical => 105/115 Series (105 Coupe/Spider/Berlina) => Topic started by: adriank on November 23, 2009, 03:49:37 PM

Title: Ignition Switch faulty
Post by: adriank on November 23, 2009, 03:49:37 PM
Gents, have hunted around previous posts and can't seem to find anything where people have had issues with thier ignition swtich on the coloumn. The context for my issue is that my one was replaced at some stage with a later model one (possibly from an alfetta) > which is now not working. If i turn it to "on" I have power and the car can be jump started but the contacts seem to have died for the part that provides power to the starter motor.

I have a late model GTJ 1974 (Series 2 i think) so the switch is on the column.

Questions
- can i buy a new one, or can the be overhauled/reco'd
- what other models fit?

Adrian
Title: Re: Ignition Switch faulty
Post by: cjheath on November 25, 2009, 10:21:23 AM
I've had success reconditioning these. You need a ball-end allen key to remove it in under 20 minutes. The body is riveted together, but you can drill those out and use 3/16" bolts to re-assemble. In my case the contacts were burnt , and a light touch with fine carbide paper fixed it. Check before disassembly, as you can get access to some of the contacts with a diamond nail-file through holes in the body.
Title: Re: Ignition Switch faulty
Post by: 1750GTV on November 25, 2009, 03:10:15 PM
Adrian,

When you get it fixed, it's well worth fitting a decent relay in the starting circuit so the contacts in the switch aren't carrying a heavy current load when the switch is used. While you're at it, fit some in the headlight circuits for the same reason - the fine contacts in the light switch pit over time causing intermittent faults and eventually complete failure.

I don't know why relays weren't factory fitted - just another aspect contributing to the overall charm of these vehicles ....

Chris
Title: Re: Ignition Switch faulty
Post by: adriank on December 03, 2009, 11:27:20 PM
yeh good points, unfortunately my headlight switches are already dead and need a recon'd set, do you know if someone locally in Sydney or Melbourne will recon the switches?

Adrian
Title: Re: Ignition Switch faulty
Post by: cjheath on December 04, 2009, 10:22:42 AM
avagoyamug! It's not hard. Once you remove it, you can almost certainly fix it using a strip of fine wet&dry paper around the end of a suitably cut-down icypole stick. There's quite possibly no need to open the unit up.
Title: Re: Ignition Switch faulty
Post by: WilliamB1750 on January 31, 2010, 09:59:36 AM
Just to revisit an old topic briefly.....
Pitting etc of the switches is not that uncommmon? My light switch is causing the tail and dash lights to flicker, yep I figured that they are on the same circuit,
and essetially cleaning the contacts etc should solve most of these issues?
Cheers
Bill
Title: Re: Ignition Switch faulty
Post by: adriank on January 31, 2010, 10:53:42 PM
check this wiring diagram attached, i dont think they are on the same circuit. I have never head or the dash lights flickering (and i have worked on most the electrics on these cars now.

Can you provide some more symptoms?

AK
Title: Re: Ignition Switch faulty
Post by: WilliamB1750 on February 02, 2010, 05:40:26 PM
Yes pretty simple really, the dash lights go out, I jiggle the lightswitch and they come back on again, and the tail lights go on and off at the same time. Checked all the earthing and its got good contacts etc.
Title: Re: Ignition Switch faulty
Post by: 1750GTV on February 02, 2010, 08:59:26 PM
I had the same problem years ago with my 1750. Wiggle the switch with it turned on and the parking lights (both front and rear), the green advisory light and the dashlights flicker on and off. In my car they all share the same fuse (5th from the left).

As I indicated previously, I fixed the problem by cleaning the fine switch contacts and fitting relays. I didn't have to replace the switch unit.

No problems since.

Chris
Title: Re: Ignition Switch faulty
Post by: WilliamB1750 on February 03, 2010, 04:34:01 PM
Thanks for that Chris, was just double checking before I started stripping things and going way to far  :)
Title: Re: Ignition Switch faulty
Post by: 1750GTV on February 03, 2010, 05:35:25 PM
It is not a difficult job but you will have to remove the steering wheel and the cowling around the steering column so you can get the switch off easily.
It's worth going this far as you can then do a good job of polishing all of the contacts. Any half decent autoelectrician can fit some good relays after you've restored the switch.
Also, as I said previously, while you are at it, it's a good idea to fit a relay in the starting circuit to relieve the ignition switch of a very heavy current load.
Once you've done this you'll never have any more electrical problems ;D
Good luck and let us know how you get on,
Chris
Title: Re: Ignition Switch faulty
Post by: Tim Jobson on February 04, 2010, 04:06:12 PM
Chris,  I have put relays in for my lights however I would also like to do the relay mod for the starting circuit.    Do you have any pictures or diagrams on the suggested way of doing this.

Thanks

Tim

PS:  My car is finally registered after 14months and had my third drive in her yesterday....lots more work to do!
Title: Re: Ignition Switch faulty
Post by: 1750GTV on February 04, 2010, 08:56:27 PM
Tim,
I rang the autoelectrician before I left for home this evening to find out what they would have done. When I thought about it, fitting an auxiliary relay in the starting circuit did seem a bit strange.
He said that virtually all cars already have a relay (the solenoid) that switches the heavy current load when the starter is engaged. All they would have done is check that it is closing properly when activated and releasing when deactivated. Sometimes they play up and respond well to a sharp smack with a hammer. I remember my Dad doing this to our old second hand EH when I was a kid.
It is possible to install another relay, but not necessary as the current flowing through the ignition switch is already fairly low. Sorry if I gave you (and everyone else) a bum steer about this one. My car, like all the others, is only equipped with a solenoid.
I do however have aftermarket relays in the lighting circuits :)

Glad to hear that your 105 is on the road - they are great fun, maybe not as much as a Ferrari, but still well worth the time and money spent.

Chris
Title: Re: Ignition Switch faulty
Post by: Tim Jobson on February 05, 2010, 11:27:52 AM
Thanks Chris, yes she will be fun to drive and own as I do not have to worry about the cost of spares, insurance or where to park it as I did with my 308!

I will post some updated photos next week of her

Tim
Title: Re: Ignition Switch faulty
Post by: WilliamB1750 on February 05, 2010, 03:02:41 PM
Thanks for clarifying that Chris, nice little job for a spare moment or 2.