MTFCA Forum

My key fits nicely into the ignition of the switch plate but doesn’t move the tumbler. I’m afraid the pot metal is swollen but really don’t want to purchase and install a new one. Has anyone had this ignition challenge and overcame it ?

Are you sure that you have the correct numbered key?
Maybe try a master key?

Assuming they key is correct.....I doubt if the cylinder is swollen (the cylinder could be split), but most likely the wafers inside may be sized. Spray some WD40 (never graphite), let it sit for a few minutes then gently wiggle the key. This article may shed some light on how things are supposed to work.

I’m using the same numbered key thats numbered on the cylinder. But I also have a master key set. I’ll try the correct one of the 3. Good idea with the WD 40 but I’ll try PB Blaster. Great information Frank ! I learned a lot !

I have found that some of the aftermarket keys are not ground accurately. Try to find an original key. Sometimes if you do find one that works, a little filing in the right places to make the one which does not work, conform with the one which works will help. If you do find one which works, be sure to remove it when not in or working on the car, so it won't get lost.
Norm

Thank you Norm. I am using an original key. The backing of the cylinder has been sitting in PB Blaster. Time to go see if it moves

Does the cylinder move at all, or is it rock solid? I don't just mean will it turn at all, but will it even wiggle around a bit, side to side, up & down, etc.?

Another thought, the pot metal cylinder can grow in diameter, making it tight, but it can also grow in length, which has the effect of not allowing the key to go in deep enough. You sometimes find a key that has had the shoulders filed back a bit to compensate for this.

Does the front of the cylinder have the key no. stamped on it? Maybe it’s worn off? But I think it should be there. Look at it closely. http://www.mtfca.com/discus/messages/41 ... 1405770514 Check this out. This post has key cylinders with the key number.

Yes, the cylinder slightly moves Jerry. Zoom in to the backside of the picture I posted. In the small vertical rectangle you can see the key front. The cylinder surrounds the ‘rectangle’ and the triangles at 9:00 and 3:00 disallows movement of the cylinder. How should I proceed to overcome ? Thanks all….

Swelling of the lock cylinder is most likely the culprit - the cylinder should turn either direction until the "stops" - mag. one way, bat. the other. If lubrication doesn't assist in operation, it might very well be toast !

George House wrote: ↑

Wed Dec 25, 2024 11:21 am

Yes, the cylinder slightly moves Jerry. Zoom in to the backside of the picture I posted. In the small vertical rectangle you can see the key front. The cylinder surrounds the ‘rectangle’ and the triangles at 9:00 and 3:00 disallows movement of the cylinder. How should I proceed to overcome ? Thanks all….

Hard to say without holding it in hand. I'm wondering if growth in the cylinder length isn't causing it to bind against the "9 & 3" tabs you mention.

George House wrote: ↑

Wed Dec 25, 2024 11:21 am

Yes, the cylinder slightly moves Jerry. Zoom in to the backside of the picture I posted. In the small vertical rectangle you can see the key front. The cylinder surrounds the ‘rectangle’ and the triangles at 9:00 and 3:00 disallows movement of the cylinder. How should I proceed to overcome ? Thanks all….

The switch is actual two switches in one.The "rectangle" piece is operated by the handle is toi control the lights. The key selects the power source OFF, BAT, MAG. there is no connection between them. The arrows pointing at positions 9 & 3 are stops to prevent the key from going past the respective positon

Frank, I moved the headlight lever from DIM to BRIGHT and it actuated that tan square paper-like component with 4 rounded corners. Not the tumbler/cylinder. But I’ll soak the latter in PB Blaster again tonight.

George House wrote: ↑

Wed Dec 25, 2024 5:36 pm

Frank, I moved the headlight lever from DIM to BRIGHT and it actuated that tan square paper-like component with 4 rounded corners. Not the tumbler/cylinder. But I’ll soak the latter in PB Blaster again tonight.

The headlight lever only moves the tan square component. The key only turns the rectangle end on the cylinder (tumbler) slightly to the left or right. That is attached to the mall circular disk.
when viewed from the back \ MAG & / BAT --
You can pry up the square fiber rectangle, carefully a little at a time. It may be stuck with some rust residue. Note the handle position.
--
The cylinder resides inside a cage that has openings, top & bottom, to allow the wafers to drop/raise when a key is inserted. When no key in in the cylinder the wafers drop down do to gravity. Some wafers are brass others steel. Some times a key need to be pulled back a hair to setup the wafers properly

Yes; I was just answering your “rectangle piece is operated by the handle to control the lights” by stating the headlamp lever actuates that square piece. If you’d lift that G shaped central component in your last photo, you’ll see the cylinder and the 2 points at 9 and 3. The cylinder (#58) slightly moves with key #58 but those 2 points prevent the key&cylinder from going to BAT or MAG. Therein lies my problem. But I greatly appreciate your illustrations when its time to reassemble the loose components.