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TR4/4A Trunk Lock Help

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bammons

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I cannot get my trunk lock to "lock" anymore. The key turns only 1/4 turn (I think it was going 1/2 turn). I did take the inside latch mechanism off and cleaned/lubed it and it was dirtier than I would have thought but did not help. So I am thinking it is a inside the cylinder problem. The key does turn easily the 1/4 turn and I did not want to force it anymore until I maybe hear from you guys. Any ideas of what is preventing it from turning further assuming it is supposed to go 1/2 turn? Bruce
 
You are right; the key should make a complete half furn.

I suspect that something in the cylinder is broken and jamming it at the 1/4 turn point. Unfortunately, I've never been able to get one of those lock cylinders apart, but with a little effort and research, you might be able to do better than me. I am pretty sure that the problem is more than just dirt.

Worst case, you may have to replace the cylinder.
 
Just to confirm, this happens when you turn the lock and the trunk is open, so it is not the latch causing the obstructions?
 
I believe I now see the problem. The chrome "bezel" that sits underneath the handle has tabs on the side which fit into corresponding notches i the sheet metal of the trunk lid. My bezel is turning with the handle and it is supposed to be stationary as the handle turns. I am having trouble identifying if the problem is my sheet metal or wear on the tabs that keep it from turning. On top of that there seems to be a second layer of sheet metal under the top layer and some it seems to be bent down a little. What I did yesterday is add a dab of JB Weld to the tops of the keep tabs on the chrome bezel to help it catch the sheet metal keeps better (I hope). Going to try that today if I can stand the cold in the garage. Bruce
 
Having a similar issue on the 250. When boot lid closed, cannot turn the key to lock the boot. Key turns fine open with handle in the closed position so the tumblers are OK. Applying downward pressure on the boot lid does not help.

FIXED: Just a bit more pressure in turning the handle closed did it, and by a bit more I doubt I could measure it.
 
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Update: The JB Weld I used really did not help much so I had to drill two holes where the bezel lock tabs are underneath to increase the length. I screwed two small screws into the holes (be careful how far you drill). I then filled under the screw heads with JB Weld. I took a long screwdriver from underneath the lid and tried to prise up the "second" layer of sheet metal (I think it is simply a reinforcement sheet). I think my metal had pushed down some. By doing these steps I have a working lock although I have to be careful with it as the bezel still moves a slight bit. The key is to get the bezel to stop turning or moving with the handle. Bruce
 
You are right Bruce - the trick is to stop the bezel from turning, as this is what the handle is 'locked' to when you turn the key. If the handle has been forced in the past, in the locked position, then it doesn't take much for the bezel lock tabs to override the notches in the sheet metal work of the trunk lid. You'd be on the right track with attempting to screw the bezel to the trunk lid, but maybe a more substantial hand-crafted inner reinforcement sheet may be the go as an alternative - assuming your bezel tabs are still in good nick.
 
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