Locked Out !!
 

ALLO.

THE 1973 MB 450 SL HAS A DEAD BATTERY, WHICH IS
LOCATED IN THE TRUNK. THE KEY GOES INTO THE TRUNK
LOCK, TURNS, BUT THE TRUNK WILL NOT OPEN.....

HOW TO SOLVE THIS PUZZLE ? HOW TO OPEN THE
TRUNK, TO REMOVE & REPLACE THE DEAD BATTERY ?

HELP !!

THANKS IN ADVANCE...

Where did you find a 73 SL with the battery in the trunk? All the ones I ever worked on started the rear battery with the onset of catalytic convertors in the engine compartment in 1975.

As to the lock. Those cars have a vacuum locking system and often the vacuum locks work when the key won't. I presume you have lost vacuum. You might be able to go to the source vacuum line under the hood and apply vacuum (suck on it if you have to - you will turn blue), and then work the locks.

In cases where nothing else works we have removed the license plate and with a second car sitting beside, we make a small hole that we use a coat hanger through. The second car is to see where to go inside the hole.

STEVE.

10-Q for the options. will leave the drilling 'til last.

Where, exactly, is the vacuum line/hose & how will I know
which to use ? How many are there ?

ps. my 75 450 sl, also has the battery in the trunk !!!

maybe a calif thing...

Try this
 

I only have a '88 560sl as reference and on this vehicle the trunk lock cylinder connection to the lock tang is pure mechanical, turning the cylinder to full clockwise with the master key will engage the tab to open the trunk. This mechanical movement will trigger the vacuum thus making no vacuum required for the lock at which you have inserted the key.

However, if your's is somehow different and requires power, connect jumper cables to the power junction on the right front fender. That should apply power as though the battery were charged.

Yellow plastic vac line in the engine compartment is the lock supply line.

You should be able to unlock the trunk with the key. However, they can be somewhat tricky (at least on my W108) -- you may have to turn the key slowly toward the unlocked position while repeatedly pushing it and the button in and out until the latch "catches" and open. Big PITA.

I'd try the vac lock system with a Mitivac before I'd drill a hole!

Peter