Fixing Sloppy Door Locks in 70s-80 Rolls-Royce and Bentley

What happens when your car won't lock or unlock?

Today's cars have pushbutton locks, but older cars don't generally have that feature. They rely on the traditional mechanical system of a key receptacle in the door, a link rod to the latch, and inside the latch, a mechanical lever to unlock or lock the door. Over 30 or 40 years, the mechanism between the key receptacle and the latch may bind from lack or lubrication, or become sloppy from repeated use.

Either way, the mechanisms on many 70s Rolls-Royce and Bentley motorcars are now in need of repair.  The latches and locks are no longer available, so we have to fix what's there. In this article I'll show the process of fixing a mechanism that had so much wear the key would turn all the way but the car would not reliably lock or unlock

We started by removing the lock tumbler, rod, and latch.  The first step is an examination of the tumbler.  In the photo below you can see the holes that contain the pins that set the key coding.  I suggest cleaning the mechanism and protecting with a good shot of light oil.

The rod that connects the lock to the latch is visible at the bottom.  In this car it's short - less than an inch.  Other models have longer rods but the idea remains the same

Here is the latch.

When on the bench the problem was evident.  The slot on the latch had worn, and the pin on the rod was worn.  Between the two parts, there was almost a eighth-turn of free play.  There was not enough movement to work the lock.

The fix is relatively simple.  A sleeve wraps around the smoothed shaft on the rod.  That sleeve takes up the slop and gives a snug fit into the latch.  It's ready for another 40 years.

Technicians who work on modern cars are accustomed to finding a broken part and ordering a new one.  It's not that easy on older cars where parts tend to be discontinued or otherwise unavailable.  The mechanisms may be simpler, but more creative thinking is required, often with a good dose of fabrication skill.

That is one major difference between a technician who rested vintage Rolls-Royce and a tech who works on new ones in the dealership.

© 2020 John Elder Robison

John Elder Robison is the general manager of J E Robison Service Company, celebrating 30 years of independent Land Rover, Bentley, Rolls-Royce, BMW/MINI, Mercedes, restoration and repair in Springfield, Massachusetts.  John is the technical editor for the Flying Lady, the magazine of the Rolls-Royce Club of America, and a longtime technical consultant to the car clubs. He’s owned and restored many fine British and German motorcars.  Find him online at www.robisonservice.com or rroc.org or in the real world at 413-785-1665

Reading this article will make you smarter, especially when it comes to car stuff.  So it's good for you.  But don't take that too far - printing and eating it will probably make you sick.