Adding Deadlocks to the Cab.

Because I intend to take my Unimog campervan to places where theft from vehicles is very common I decided to add a deadlock to each cab door. Unlike the standard Unimog door locks these deadlocks can not be opened from inside the cab. This means that if you gain access to the cab by breaking a window you still have to climb in and out via the broken window.

The locks I fitted are D125 Multi Bolt Locks from Safeways Ltd. and are specifically designed to fit within the door cavity of many vans and trucks. Because fitting them requires that you drill big holes in the door panels of your Mog and as the locks do not come with exact fitting instructions for a Unimog the description below is fairly detailed in the hope that it may help others.

The door interior trim panel is removed by unscrewing the window winder and pulling out the "fir tree buttons" that hold it in place.

Unless very great care is taken many of these "fir tree buttons" will break.

Replacement buttons can be obtained from Components Direct.

The D125 lock comes in two parts. A 100mm long barrel with three spline holes. (With a U1300L door the centre hole is used for the lock spline and the farthest (right) hole is used for a stop spline.)

The lock proper fits thru a hole in the door panel and its spline engages with the bolt.

The barrel is fitted in the edge of the door 115mm below the bottom of the door handle mounting nut and 63mm in from the door lip.

A hole "about" 19mm is required (the instructions are vague and the barrels seem to come in a variety of sizes). Because I did not have a drill/bit of this size the hole had to enlarged with a rat-tail file.

Although self tapping screws are provided with the lock I used 15mm M4 bolts and locking nuts.

Because of the position of the window opening mechanism within the door fitting the M4 nuts is tricky.

Finding the correct position to drill the hole for the lock is best done using wide masking tape wrapped round the door with the top edge lined up with the centre of the barrel.

The lock should be centered 74mm in from the edge of the door. This position algins the lock with the centre hole of the barrel.

The lock hole has to filed out to size and shape so as to fit the stop plate that prevents the lock rotating.

Because the spline attached to the lock is too long to fit within the door cavity it must be shortened before the lock is mounted.

Assembling the lock and locating the spline in the central hole of the barrel within the the confines of the door takes time and patience.

As can be seen (right) the lock and barrel are very close to the window channel.

In order to locate where on the door pillar to drill the hole to accept the bolt the best method seems to be to stick five or six layers of masking tape to the door pillar and then operate the lock forcibly against the layers of tape.

The resulting depression in the tape can then be used as a guide to where to drill. The supplied plate is then be secured using self tapping screws.