If your Bentley Azure or Rolls-Royce Corniche makes a heavy
clunk from the front end the problem may be failed upper strut bushings. In those cars the struts keep everything
centered in the spring/shock assembly.
When the upper bushings fail the shaft of the shock rattles loudly
against the top plate for the strut assembly.
You can often see failed bushings from under the hood. The photo below shows an assembled strut top,
and you note two things. First the shock is off-center in the larger hole,
indicating the bushing is no longer holding it in place. Second, you can see a torn edge of the
bushing.
The next photo shows what you do about that problem. It’s a situation where the repair is plainly
visible when opening the hood, but fixing it takes all day. In my hand you see two replacement bushings (note they are different with the one with the collar going on the inside.) To change these you’ll need the factory spring compression
tool, which squeezes the spring and allows the strut rod to be pushed down.
This is what the lower bushing looks like, once the strut is disassembled. You can see how the round hole has become an oval and the strut is pushed sideways where it bangs over every bump
These rubber bushes are sandwiched between heavy steel
washers. One washer is visible with the hood open, the other is hidden inside the strut.
Rolls-Royce used this strut system from the introduction of
the Silver Shadow series in 1965. On the
older cars you could make a short-term repair by installing an aftermarket
bushing under the top washer, without strut disassembly. That worked through the mid-1990s when the
Crewe engineers changed to the heavier bushings.
This photo shows the strut in place with the tool installed, from below:
Nowadays we install the tool and clamp the spring. We lift the spring, bushing, and sleeve out of the fender well, leaving the bare strut in place as shown
We replace the bushing, which is shown inside the spring assembly in this illuminated close up:
The bushing is held in place by a rubber gaiter that covers the top of the assembled strut. When the strut pulls out from below the gaiter remains inside the spring. Once changed the spring goes back into the car and the strut pushed through from below. Then the upper bushing and washer go on and the whole thing is screwed up tight. Then the spring tool is removed and the job should be done.
© 2017 John Elder Robison
John Elder Robison is the general manager of J E Robison Service Company, celebrating 30 years of independent Bentley, Rolls-Royce, BMW/MINI, Mercedes, and Land Rover restoration and repair in Springfield, Massachusetts. John is a longtime technical consultant to the car clubs, and he’s owned and restored many fine British and German motorcars. Find him online at www.robisonservice.com 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.
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