vacuum locks jammed.
 

Hi,
I'm new to the forum so please bear with me. I have a problem with the lock on the trunk of my 71 280s. over the years, the vacuum system has gradually failed me, and right now nothing to do with locks is working. The first thing to really go was the trunk. I actually broke a key off trying to get it to unlock, so I opted to drill it out (mental note: don't take a drill to your mercedes if you don't have a clear idea of what your trying to achieve). After drilling a 1/4 inch hole in the lock cylinder, I went bigger. Right now, the lock cylinder is completely mangled with about a 1/2 inch hole right through. You can turn the whole tumbler thing around with an easy-out, but this has gotten me nowhere.
I would really appreciate it if someone could give me some information on how to open the trunk. I have considered going in through the back seat, but I want to know if there is an easier way before I destroy something else. In the end, I'm going to need a new lock cylinder, so if anyone knows were I could get one of those that would be great!
Thanks for your time, there is a lot of information and knowledge available on this forum,
Riley

Can you push the button in?

Yes, I can push what's left of the button in, but it doesn't spring back. I have to push and pull with pliers.

The trunk releases when the back of the lock mechanism pushes on the latch (mounted on the trunk lid) and moves it away from the plate (on the body). I think the vacuum actuator works by pivoting the piece on the back of the latch so that it doesn't make contact with the latch when you push the button in.

So you may need to keep going with your drill (carefully) until you get enough of the old lock out that you can push the latch in.

Attaching a picture from the EPC that may help you visualize.

Drill from a 7 o'clock position to a 2 o'clock position. Then the guts can be removed without damaging the back of the lock barrel.