Convertible Top Repair in Bentley Azure / Rolls Royce Corniche

Convertible top hydraulics are shaping up as a major weakness in the Bentley Azure and Final Series Corniche from Rolls Royce.  These cars were built from 1996-2004 (a newer Bentley variant remains in production today) and all are vulnerable to this issue.

The Bentley Azure and RR Cornice are fine cars but the tops are a weakness (c) J E Robison

Here’s the problem, in a nutshell.

The engineers at Crewe wanted to design a fully automatic convertible top for the new Azure series.  But they did not have the resources to do a new design; they had to adapt something else that was already out there.  The Mercedes SL500-type design was well regarded, and they chose to adapt it to the Azure body.

Unfortunately, the design didn’t work as well on the RR/B.  It’s remarkably reliable on the Mercedes, and astonishingly flimsy and incredibly costly to fix on the Azure.  What went wrong?

There are a few essential problems.  First, the systems use very high hydraulic pressures.  Older automatic tops used big cylinders and rams.  With several square inches of ram, you don’t need very high hydraulic pressures to generate the force to move the top.  However, the newer cars use tiny actuators hidden in the top. They are smaller, so the hydraulic pressure needed for a given actuation force rises.  Because the hydraulics are hidden, they are often at a mechanical disadvantage (leverage in reverse) and need to push harder to move the top.

The result:  hydraulic pressures on a 2001 Bentley convertible top can run almost 10 times as high as the pressures on a 1987 Bentley convertible top.  With that factoid in mind, it should not surprise you that the newer tops are not as reliable.

In addition, the newer tops use automatic latches instead of human power to pull it shut and locked.  Those latches are not as rugged as they should be.  Why, you ask?  Look at a Bentley Azure and then look at an SL500.  What do you see?  The Bentley top is significantly larger.  That multiplies the forces on every component and it’s one more reason a reliable Mercedes design didn’t work out the same on the RR/B.

The next problem probably started in Crewe’s engineering department, though I doubt they would admit it.  Mercedes uses plastic lines that are impervious to hydraulic fluid, but that material selection did not translate to RR/B. Someone there chose a hose material that deteriorated with contact with hydraulic fluid.  The result – when they get to be ten years old you see the black rubber casings falling off the hoses, and blowouts inevitably follow. 

How do you check your convertible top hoses?  Look at the hoses in the main hinge area when the top is partly lowered.  Here are examples of hoses that are coming apart.

The upper photo is a closeup of jacketing peeling from a hydraulic hose.  Failure is imminent (c) J E Robison Service

If this problem is ignored you will see leakage, as evidenced by the leaked oil in these photos.

Leaked hydraulic oil in the convertible top well (c) J E Robison Service

Oil seeping from the convertible top hydraulic line bundle 

If you ignore it even longer, you will eventually be showered with oil when a line blows under pressure and the interior of the car is sprayed and damaged.

Header bar line with deterioration.  These are the worst if they blow

"Green showers" most often come from the header bar, when the lines above the rear view mirror blow out.  The reason those lines are the first to blow is that area takes the most beating from the sun. In a hot climate that area can be over 200 degrees all day, and the oil they originally used breaks down into a green jelly that won't pump, and causes pressure surge and blowouts.  Jaguar is known for having this problem too.

The new hydraulic oils are synthetic and they resist this, but the moral there is - change your top hydraulic fluid every few years, or else.

When the top is partly folded there is another thing you want to check – the cables.  These new automatic tops need to fold into a tight space to be hidden under the rear deck.  To do that they rely on cables sewn into the top lining.  Loops of wire around those cables pull the top fabric against the bows and fold everything properly.  If the cables break the top will jam in the bows, and if the bows bend as a result – you have big trouble.

Broken stay cable on Bentley convertible top

In most of these cars you will see leakage from the hydraulic actuators in addition to problems with the lines.  Here is a set of actuators removed for service.  We rebuild these units rather than replace them.

So how do you fix this?  You remove the trunk lining, and the pump and lines.  Open the convertible top boot and remove the top as an assembly. Remove the cover in the convertible top well, and unthread the lines there.  Remove the rear seat, both side panels, the right side floor covering, and the right side dash and windshield pillar trim.  Remove the windshield header bar covers.  Remove the lines and remaining actuators.  Replace and reassemble.

Sounds easy?  Look for a job time of 60-90 hours, more if you are not experienced or run into trouble.

In the next convertible top installment I will begin to cover the actual repair process.


This article is about the automatic convertible top system used in Rolls Royce and Bentley Azure and Corniche from 1996-2005.  Check out this article for thoughts on the newer Bentley GTC convertible top and its problems

And here's an article on 1997-2005 Jaguar XK8 and XKR convertible tops - they have some of the same issues but are simpler to fix

Good luck

John Elder Robison

Robison Service has provided independent service, repair, and restoration for Rolls Royce -Bentley owners all over New England for over 25 years. Founder John Robison is a long time technical consultant for the Rolls Royce and Bentley Owners Club. Our company is an authorized Bosch Car Service Center. We also service Mercedes, Jaguar, Land Rover, Porsche, and MINI motorcars. We have flatbed transport throughout the northeast region, and we work with Intercity and other transporters for greater distances. We also offer pickup and delivery for cars in  Springfield, Wilbraham, Longmeadow, Agawam, Westfield, Northampton, and Amherst.  Our drivers are available to pick up cars in Boston, Hartford, Greenwich/southern CT, New York, Rhode Island, Vermont and New Hampshire.

Restoration and the future for Rolls Royce and Bentley cars - the 2014 RROC Annual Meet at Seven Springs

This past week I attended the annual meet of the Rolls Royce and Bentley Club at Seven Springs resort in southwestern Pennsylvania.  I’d been invited to give a talk on care and feeding of what the club calls Modern Cars (principally the vehicles made from 1965-1999.)   Other technical people did presentations on older cars, and there were additional sessions on Modern Cars too.  Factory personnel were there to show off the current product lines, and vendors were on hand with books, parts, and obscure restoration materials you never knew you needed, and could never find outside an event such as this one.

Silver Clouds parked at Seven Springs Resort for the RROC 2014 Annual Meet

Behind it all was Pennsylvania’s version of a ski mountain, which turned out to be significantly steeper and higher than it looked as soon as I set out to walk to the top.  When I finally attained the summit I was disappointed to discover the event organizers had cancelled the vintage car hill climb I’d come to see. I had been looking forward to the sight of antique Silver Ghosts racing up the ski trails, throwing great gouts of mud and debris in their wake.  Maybe next year’s meet in Orlando can feature a good old southern Swamp Run instead.

A view of the slopes at Seven Springs

With organized mayhem cancelled I found myself wandering the parking lot, admiring the attendee’s vehicles and wondering what might have been.  There were cars of every era on hand, from the earliest Rolls Royce models to the latest Bentley sportsters.  Over one hundred years of automotive history was there on the grounds.

The cars were parked by rough order of age, which made walking across the lot roughly akin to taking a journey back in time, from the present day to the first decade of the 20^th century.  I wondered who had owned the grand tourers of the twenties, and where they had been.  I wondered where I will be, when I am their age.  I’ll be doing very well to be sitting on tarmac like them, and not buried beneath it.

As I wandered, I realized the groups of cars provided an interesting window into how restoration affects a vehicle population, both in terms of condition and value.

Cars built in the last decade were almost all original, and many remained in near-new condition.  These cars were not really “collectibles;” they were simply expensive used vehicles. Unlike their older siblings, no curation or restoration was needed to keep them nice.  A cool shady garage and regular maintenance will do the trick to preserve these specimens for quite a few years.  None of these cars were restored, as far as I could tell, though some had significant refurbishing.

There were some very fine examples on the show field. You could not miss the enormous effort some owners have put into keeping their late model cars in stunning condition.  That surely has costs, both in time and service expenses.  But those costs are far less that one would pay to put, say, a 1920s Ghost into similar shape.

With care, Bentley and Rolls Royce cars can last 20+ years in original condition

Most of the cars from the 90s were showing some wear, and some refinishing, but many were still in nice original shape.  Quite a few of these cars had been painted, and some had new interior trim.  Many of these cars had received significant mechanical service, while others were obviously badly in need of the same.  Once again, I did not see a single restoration though I did see plenty of well cared for cars.  With continued good care some of these cars may remain nice for a good many more years.

With so many good mostly original examples to choose from, few people will choose to restore these cars at this time.  If your goal is to "get a good one" that can be done by careful shopping.  Those who want to restore grandpa's Bentley will not care about finances and are unaffected by this tradeoff.

Cars from the 80s still showed a lot of originality, which meant many examples were looking somewhat long in the tooth.  There were quite a few “fixed up” cars – vehicles with good repaint jobs, redone woodwork, and the like.  These cars were not restored, but they had received significant repairs – mostly to paint and body. If this sample is an indicator, true restoration of 1980s cars has yet to begin on a wide scale. 

70s cars - the transition zone

Silver Shadow cars from the previous decade (the 70s) were the roughest of the bunch.  There were some very nice examples, but even the nicer looking cars showed heavy signs of aging under the hood, and many showed body and interior wear too.  Clearly, these cars are at or close to the Decision Point age.

The Decision Point age is when you realize the “fix it later” issues cannot be put off any longer.  The car has worn down to the point that it's worn out.  Often the point is reached after a major breakdown, perhaps stemming from deferred upkeep or outright neglect.  What then? Do you fix the car up properly, scrap it, sell it, or put it in storage for a decision another day?

At least one of the Shadows at the National Meet was beyond the Decision Point, with a very nice restoration.  We have another such car in our shop now, which we hope to show at an upcoming meet. Shadows in that range remain rare.

Many of the older, rougher cars would be described charitably as “twenty-footers” while more direct critics would call them rats.  In talking to the owners the problem is apparent.  Book values are low.  Restoration costs are high – way above book.  And many owners lack the means (either money or mechanical ability) to really improve their vehicles.  Just staying even on these cars is a challenge as reliability has gotten so poor. 

Then we step back a decade and everything changes.  We move into the Cloud era and cars of the late fifties and early sixties. Many of those cars had been beautifully and lovingly restored, and it showed.  It was also apparent in values.  Edgy 1970s cars are lucky to fetch $10,000 while magnificent Clouds – just a few years older – bring solid six-figure prices at every classic car auction.

Cars like this Cloud III drop head have skyrocketed in value this past decade

What happened?  We found the transition point in vintage Rolls Royces – the 1965-80 range.   Good examples that are newer will be mostly original.  Rarity isn’t a big factor in cars of that age. Consequently, prices will be based on depreciation from new, and the cars are almost 100% depreciated. The situation is totally different for older cars.  Prior scrappage and lower production in earlier years has made these cars a lot rarer.  For the most part, they are too old to be driven in totally original form.  The best cars are show-quality restorations, and it is these vehicles that set the prices for the class.  If it costs six figures to restore the cars that raises the former $20k "good" used car prices through the roof, seemingly overnight. 

Even the “low value” cars in this age range are getting quality restorations, and that is lifting all values significantly. The question now is when that will happen with the Shadow and newer series.  If a restored 1964 convertible is $300,000, an unrestored 1968 convertible starts looking pretty good at 1/10^ththe price.

But unless that happens on a wide scale, cars in the transition zone are at risk.  Most are in need of significant repair as resale values have sunk to a fraction of repair cost.  Any major repair – paint job, engine overhaul, new interior – is likely to exceed book value.  A few owners are making the investment anyway, because they happen to like these cars.  The question now is which way the trend will go.  Will owners (either current owners or new owners) restore these cars, or will they end up recycled?

Owner demographics come into play.  The owner who stretched to realize their dream of buying a $10,000 Shadow is not likely to undertake a $150,000 restoration of the same car.  Yet a project of that scope would be far less costly than restoring a blower Bentley car from the 1920s, and those owners routinely do such jobs.

Silver Ghost chassis in mid-restoration, at RROC Ghost University

A Rolls Royce Silver Ghost engine

What it takes to restore a chassis - Silver Ghost or Silver Shadow, the job is the same

A run-down and mostly original 1960s sedan fetches $10,000 at auction. As noted earlier, a restored Cloud convertible may bring $300,000 or more at the same sale.  Restoration of these older cars is justifiable and increasingly common as values continue to rise.   Cars of the fifties and sixties are today’s target for high end restoration, but the 70s cars will have their turn any day now.

If I were betting on a future collector market for Rolls Royce, I’d put my money in the seventies.  The older cars have already made a dramatic ascent.  Newer cars are still falling in price.  The 1968-1983 range may be just right.  Buy good ones at these prices while you can!


John Elder Robison is the general manager of J E Robison Service Company, independent restoration and repair specialists in Springfield, Massachusetts.  John is a longtime technical consultant to the Rolls Royce Owner's Club and other car clubs, and he’s owned and restored many of these fine vehicles.  Find him online at www.robisonservice.com or in the real world at 413-785-1665

Rebuilding Brakes on Vintage and Collector Cars

The last of the Crewe-built Bentleys

Rebuilding a rear brake caliper on a vintage Rolls Royce 

Brake jobs used to be so simple!  Pop a set of pads into the calipers, and you were good to go.  No more, especially on high end cars like this Rolls.  Let’s look at what goes into a quality brake job on a classic high end car like this, using a 1980s Rolls Royce as an example.

When a car is new, everything moves freely and it’s easy to do routine service.  For the first service you can often still do pads only, but it gets more complex from there.  By the second pad change the car is certainly ready for new rotors.  When do you need rotors?

There are three reasons you may need new rotors:

1 – They are worn below the minimum safe limit, as marked on the rotor

2 – The rotors are out of true, and the car shudders when stopping

3 – The rotors are glazed with rust, so braking effectiveness is lost

Here is an example of a brake rotor showing both wear (1) and rust glazing (3)  This deterioration is all on the inside. The other side - facing the wheel - looked remarkably good.  Don't be fooled.

Rust on a brake rotor makes it slippery

When working on vintage cars 2 and 3 are common, but you see cars with 1,2, and 3 all together.  Rarely do you see (1) by itself. 

Measuring a brake rotor to see if it's too thin.  The numbers tell the story.

On most mass produced cars the rotors pop off with a few minutes work.  Not so on a Crewe-built (pre-1999) Rolls Royce or Bentley.  To get the front rotors off you are looking at a few hours work to remove the two calipers off each side, then the pipes and then the hub.  Once the hub is off the rotor itself can be removed with the whole thing clamped in a vise.

Separating brake rotor from hub - Rolls Royce Shadow

The rear hubs are a much more complex affair.  You need a special RR/B hydraulic puller to get the rear hubs apart, and to get them off the car.  Once they are on the ground the disassembly requires a press and various accessories.

Don’t be surprised if you find years or decades of neglect when you pull rear hubs.  Totally rotted rotors, and ruined bearings and races are common because some less-service-oriented people put difficult jobs off till “later” and later never comes.

On a newer car you’d just pop a rotor on at this point, but these Crewe RR products are old enough that shortcuts will come back and bite you.  We suggest removing and examining the wheel bearings, and replacing them if they are anything less than flawless.  In most cases, they are at the ends of their lives.  Don’t forget to do the seals.

Worn out wheel bearings and seals

We pack hubs with modern synthetic grease; all the hub rebuilding is done off the car on the bench.  Otherwise the process of bearing service is much the same as thirty years ago.  We use drifts to knock out the old races, and a press to set the new ones in place.

Rebuilt rear hub ready to install

We suggest splitting and rebuilding the calipers on any Rolls Royce that is more than fifteen years old because leakage is common when they get past that age.  And when one leaks, they are all ready.

Rebuilding brake calipers

When the calipers are apart consider refinishing the caliper bodies using the new hi-temp powder or ceramic finishes.  That’s what they do on newer high end cars and it’s a very attractive touch

Rebuilt hub, new rotor, and rebuilt and refinished brake calipers

If your hoses are more than 10 years old you should replace them.  Hoses rot from inside and old ones may blow with no warning.  

New brake hoses

Most owners of collector cars have paid for more than one brake job on modern luxury cars.  How does work like this compare, in terms of cost and time?  The short answer is . . . expect way more of both.

When you do brakes on a modern car the only parts are the pads, rotors, and ancillaries like anti-rattle clips.  On a vintage car the job may include bearings, seals, hoses, caliper parts, and even new hardware.  In addition, hard to get classic parts may be more expensive.  Finally, there may be quality problems.  You can be sure of getting quality brake parts for a late model Mercedes or BMW simply by going to the dealer.  For an old car that may not be an option, and the mail-order stuff can range in quality from wonderful to total junk.  

In general, you get what you pay for.  Here's my rule of thumb:  If you have to choose between five versions of a part (like brake pads) from known reputable vendors and the prices vary widely, the quality will vary just as widely.  You are a lot less likely to get burned buying the top priced part than the bottom priced one.  When prices for the same part range from $29 to $199 the $29 part is usually junk, and the $199 part is probably topnotch.  I know that's not what some people want to hear, but in my experience it's true.

When you fit low quality parts you are asking to do the job over, sometimes with additional damage.

The time to perform the additional steps I outline above can add up too.  Pulling and assembling the rear hubs on a 1970s Rolls Royce or Bentley is a solid two days of work.  And teardown can expose unknown problems, which may need dealing with now.  Rebuilding front hubs is more than a day's job.  Rebuilding the calipers will be another day and a half, plus the time and expense of refinishing the caliper bodies if you decide to do that.  

Rust and corrosion can double those times on cars that have run on salty winter roads.  On a classic car where parts are scarce you may spend days getting corroded stuff apart without damage because it's simply not replaceable at any reasonable cost.

And here's one more thought to consider:  Most people who service late model cars know the owners have limited ownership horizons. They will not own the car they' re fixing today in 1 year or 2 or 5.  Things that may wear out "later" will be someone else's problem.  Not so on the collector car your dad purchased and your son now dreams of owning, when you are old.  For that person, service must be done to a high standard, with a view toward a far distant horizon.

I hope this makes clear some of the additional challenges we face when doing a seemingly common service on an older car.  

John Elder Robison is the general manager of J E Robison Service Company, independent restoration and repair specialists in Springfield, Massachusetts.  John is a longtime technical consultant to the Mercedes, BMW, Porsche and Rolls Royce Owner's Clubs, and he’s owned and restored many of these fine vehicles.  Find him online at www.robisonservice.com or in the real world at 413-785-1665