Potentially "shocking" Experience: Solenoid?

[svenedin]

As some of you will know, I am slowly restoring my 1969 Convertible after many years off the road in the garage.

Today, I decided I would get the fuel mixture right having refurbished the carburettor. The car started as usual, with lots of choke, and I started making adjustments. Naturally, the car stalled a few times during this and I had to restart. On about the 5th restart, the starter motor would not stop whirring. I turned the ignition off but it still would not stop. Luckily, I had installed a battery cut off (see photo) so I was able to cut the power but there were loads of evil sparks because the battery was delivering high current to the starter motor. If I hadn't got the battery cut out I'm not sure what I would have done because it would have taken a while to get the battery terminal connector off and it would have been dangerous.

The whole thing scared me. I am really annoyed because the solenoid is a brand new Lucas branded part. Presumably the cause of these problems was the solenoid switch sticking shut which would explain why power was going to the starter even with the ignition off?[frame][/frame][frame][/frame]

[bmcecosse]

There is 'Lucas' and there was 'Lucas' - not the same thing..... These square solenoids of recent supply are not getting a good reputation, shall I say.... Find a good/old round solenoid....much more likely to last the pace...

[svenedin]

Yes indeed. Needless to say I have taken this up with the vendor (ESM) but I may send a "snotogram" to Lucas as well.

If I was just an ordinary motorist, with no mechanical savvy whatsoever (I don't have much as it happens) this could have been quite a nasty event. I suppose something would have overheated and gone bang soon enough. I don't think batteries enjoy delivering large currents continuously. It would not have been fun if there had been a fire or if I had been burned or electrocuted trying to disconnect the battery.

I replaced the old square (with push button) solenoid about 25 years ago but these are not available new (and I can't find an old one either). That replacement was bust also when I came to start the restoration. The old ones failed with the switch open which I thought was the only way they failed......never occurred to me they could fail closed after only 10 starts or so! Pathetic.

I think the round solenoid needs slight mods to make it fit with the Lucar connectors I have. As I recall it is designed for ring type connectors? Also I don't think it is OE for the age of car.

[bmcecosse]

I'm pretty sure round would be OE for any Minor....

[svenedin]

Ok. In the Moss Caralogue the square type is listed after certain serial numbers. The round type (key start) is listed as an alternative. I do have a (new) round type, key start, with push button, Lucas, but it lacks spade connectors. I am unwilling to modify my wiring but could perhaps modify the solenoid. Unsure how though. I did experiment with taking the tags off a broken coil to use as spade connectors and using the larger tags from the square solenoid but I wasn't happy with it. There was no plastic in the way to prevent the tags from rotating and shorting. Unlikely but didn't strike me as good enough.

[philthehill]

The round type starter solenoid with the push able button is available from Holden http://www.holden.co.uk stock number S7051
You should be able to take the spade terminals off the old faulty solenoid as the main current and secondary ones are secured by nuts and spring washers. On both types of solenoid the spade connectors are held from rotating by the squared off moulding around the terminal.
My round Lucas solenoid has a lucar spade terminal for the wire from the starter switch which your square solenoid appears to have. You should be able to mix and match to get round the problem without having to butcher your wiring.
The spade terminals on a coil are not up to the job.
Several years ago the pre-engage starter on my diesel Citroen BX starter would not disengage after starting the engine which resulted in a serious fire in the wiring loom. The only way I could stop it from continued turning and stop the engine was to lift the bonnet and quickly cut the main power feed cable from the battery.
It was pretty scary at the time as it is not always the best thing to lift the bonnet when a fire occurs under it. But it had to be done!

[bmcecosse]

The quality of any modern solenoid is unknown....the Holden ones may be fine, they also sell round ones... But perhaps they all come from the same far away factory..... A good old round one would be best - but I don't see any on ebay... No harm asking on here !

[svenedin]

ESM have agreed to replace the solenoid without quibble and will be taking it up with the manufacturer.

[bmcecosse]

I trust they can speak Chinese !

[svenedin]

Perhaps I should have said "distributor" i.e. Lucas.