Trunk Lock Stuck

[TomandAlex]

1980 Fiat Spider. No issues with the trunk lock before last fall. All of a sudden the lock won't unlock. I needed something in the trunk and got lucky. Pressed somewhere on the trunk and the lock unlatched. I briefly looked and didn't see anything out of the normal and thought maybe the box might have been putting a bind on the trunk making the lock not want to unlatch. The car has been garaged since then and I went to unlock the trunk last weekend as I keep a battery charger in the trunk and of course the lock doesn't want to open. I tried the pressing trick and that hasn't worked. Tried some WD40 which didn't help. The key is literally bending when I try to turn it in the lock.

Anyone have ideas other than the drilling trick?

Thanks
Thomas

[18Fiatsandcounting]

It's a tough situation to be in. One trick that I have thought about but never actually tried, is some sort of rapid vibration against either the lock or the latch mechanism. Either an air impact hammer, or perhaps a hammer drill.

Put a block of wood up against the rear valence or the trunk lid to protect the car body/paint, and vibrate the whole area as you try to turn the key. Likely requires 2 people.

Sorry, this is all that I can suggest at this point. When you do get it all apart, clean the whole mechanism including the lock, and I use lithium grease on the latch mechanism and powdered graphite on the lock tumblers.

-Bryan

[spider2081]

I have had better luck having a second person press down on the trunk while i concentrate on turning the key. Care is needed not to break the key in the lock. On my Spider the key turns counter clockwise to unlock.

[TomandAlex]

Minor miracle. I was able to finagle the trunk open. I didn't close it. Now trying to determine what is preventing the key from turning? I'm able to manually "lock" the trunk mechanism and manually open the locking mechanism. Key is still having a hard time turning and not that I've been able to unlock the trunk with the key again, though I haven't been able to work on the trunk lately. Any ideas?

OH and the battery charger that I thought might be in the trunk was not in the trunk... of course.

[spider2081]

Minor miracle.

Reminds me of a song ABBA sang "I believe in miracles"
On some Spiders the key can not be removed from the lock unless the key is in the locked position. Maybe something with the tumblers is hanging up. I have had good luck spraying brake cleaner into the lock (where the key would be inserted) then inserting the key a number of times. Each time wiping the key clean with a cloth or paper towel. I do not like spraying oils into the lock as they can gum up the tumblers over time.

[TomandAlex]

Well not sure what happened, but I went out to work on the trunk lock yesterday, inserted the key and the lock turned. So I manually latched the lock (without closing the trunk) and the key tripped the mechanism to open the trunk twice. Then the key would still move the lever but not enough to trip the locking mechanism. I thought MAYBE having the metal latch in the locking mechanism might make a difference, so I removed the latch from the trunk lid and inserted it into the locking mechanism. Every time the key opened the mechanism. Put the latch back on the trunk and tested it by closing the trunk and they key opened the trunk just fine? Not sure why the lock was hung up for a few months. Maybe the lube I sprayed on it actually took a few months to loosen stuff up? I doubt it.

[JBeau]

I've had issues with the trunk latch bending up and not seating in the lock mechanism, which has caused the trunk to be unlockable, sort of the opposite issue that you're having. The rear support of the trunk lid had at some point caved in slightly, putting the box end of a wrench on the latch and pulling gently downward helped bend it back into shape.

When I got my car, I was having similar unlocking issues. As suggested, lubricating all parts of the mechanism helps greatly. I also tightened the nut around the lock cylinder, since it was rotating in the direction of the key turn, making it impossible for the key to reach the tumblers in the lock.

[TomandAlex]

Well I cleaned the mechanism. It was working manually really well (wasn't really not working before I cleaned it.) Made sure the key would open it before actually closing the trunk. All working well. Closed the trunk and it worked. Showed the son the next day and it didn't work. I also had a different key. Used the same key I used the previous day and it worked. Dunno. Both keys turn the mechanism just fine.

[ORFORD2004]

I push on the top of the trunk over the latch when i turn the key.