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MG MGB Technical - Ignition switch removal

I have a faulty ignition switch in my 70 BGT. It works sometimes but less and less frequently - usually failing at the most inopportune time. Can someone give me a step by step procedure for removal of the switch.

Any recommendations for purchasing a new switch? Is the Moss unit any good?
LS Sheldon

Which switch have got fitted? In the dash cemtre or the optioal steering column lock switch.?
jim soutar

U.S. cars have the steering column ignition switch combined with steering lock.
LS Sheldon

LS. Remove the steering column cowl. Normally, this requires that you remove the steering wheel first, but I have been told that certain aftermarket wheels allow the cowl to be removed without having to remove the steering wheel.

With the cowl removed, you have access to the ignition switch which is held in place by two bolts of the "torque to breaking" design. This leaves two headless bolts to be removed if you want to remove the entire switch, tumbler assembly and hold down. Use a cutoff wheel in a Dremel style tool to cut a cross slot in each headless bolt, allowing a screwdriver blade to be used to remove them. Disconnect the wiring at the plug in connector under the dash.

The bolts used to hold the switch assembly to the steering column are a standard size, 5/16"-18 UNF, and the factory bolts can be replaced with either a hex head machine bolt or a socket head cap screw with no problems when reassembling the part.

Installation is the reverse of removal. If removing the switch from the attachment mechanism, there is one small cross point screw which holds the plastic switch in place on the bottom of the left hand side of the attachment assembly.

As to the quality of the Moss parts, the ones I purchased worked poorly, even after lubrication, and quit working within a year of purchase. No warranty on the electric parts after installation. I found a good, used assembly and installed it. No problems since that time.

Les
Les Bengtson

Les is, of course, correct on an ignition switch removal. Have you checked the switch? More often than not a "faulty ignition switch" is a loose connection on the solenoid. A dirty or loose connection can lead to intermittent switch failure.
John Zajac

Les,
Thans for the detailed description. I have the stock steering wheel. It looks like the cowl splits in half held in place by two screws. Before I start yanking the steering wheel off I thought I should clarify that point.

John,
Good suggestion, I will remove and clean all connections leading to the starter.

Fortunately the starter engaged for me to go to MG's by the Bay, San Francisco MG show. 75 cars exhibited from a J2 to 1980. We won the Daily Driver class. The GT did not disappoint us, started after a few clicks and we drove home only to not work again when arriving.

Lee Sheldon
LS Sheldon

If you are referring to the ignition switch only then all that holds it in place is a small screw. The lock assembly requires removing those two special screws with out heads. I have been lucky on several occasions to loosen them with as sharp center punch.
Sandy
SANDY SANDERS

The switch is the problem. If I could remove it without the entire locking mechanism it would seem easier.

Lee
LS Sheldon

"Yanking the steering wheel off?" The cowling is two halves of a plastic shell. Yes, there are screws set inside the holes you'll see. I've had occasion to get into both my '72 and '73 and the steering wheel remained in place.

Once my steering wheel lock failed (due to age) on a long trip and for several days I drove with the cowling off and used a short screwdriver to twist the ignition switch. In terms of security, at least it happened on the GT and I had a "Club" style anti-theft locking bar.
John Zajac

Lee. You will probably find that there are two screws, one on top and one on the bottom, near the top of the steering column cowl. Then, there are two screws further down, one going in from each side, which need to be removed.

Les
Les Bengtson

"started after a few clicks"

What's clicking? If it is the relay or the solenoid then the problem isn't the ignition switch.
Paul Hunt 2010

Paul,
Sorry for the misleading terminology. There is no sound coming from the solenoid or any other part of the ignition system. What I should have said: Turning the key to the normal starting position a number of times would not activate the relay, solenoid or starter, finally after about five attempts of turning the key the car started.
Lee
LS Sheldon

A few days ago you said "I will remove and clean all connections leading to the starter." which sounds to me like you haven't yet (or hadn't at that time) proved it to the switch. If bridging the brown and white/red at the ignition switch doesn't cause it to crank then the problem isn't the switch
Paul Hunt 2010

The electrical part of the switch can be easily removed. There is only one miniscule little screw holding it in the steering lock body. Unscrew and simply pull the switch body from the lock body.
Sandy
SANDY SANDERS

I checked all connection and they were clean and secure. Since there seems to be concern with the quality of the Moss switch I located a used one and installed it. At this time the car starts with every turn of the key.

Thanks to all of you for your comments.
LS Sheldon

check and clean the connection to the starter solenoid. If it works then 'seal' the connectors with silicone sealer.You'll be amazed how dirty it can get.
I'd like to claim this fix but it was the AA man who was the hero on a very rainy night, when exactly the same happened to us. That was years ago no problems since.
r Tudor

This thread was discussed between 09/05/2010 and 11/05/2010

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