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Discussion Starter · #1 ·
I picked up a non running 1991 Silver Spur to work on in my auto shop class. I'm just in beginning stages of trying to figure out what is going on with the Rolls. Before I was a teacher I worked in the automotive repair field for over 30 years so this is probably not out of my league hopefully but I'm not familiar with Rolls Royce. With that I may have a few questions when we get into the troubleshooting. We started by changing the oil and draining out the 12 years really dark gas. This week fresh gas and see if the fuel pumps are coming on then who knows. Thanks in advance.
 

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As a teacher there is always something to learn. The factory workshop manuals are your textbooks with valuable info to help you with your new motorcar.
The Bentley Heritage site has workshop, service bulletins and parts diagrams. Enjoy.
 

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The hydraulic system is the big difference in Rolls and other cars you may be familiar with. Think of it this way-
There ae 2 hyd systems in the car #1 and # 2;
Both systems have their own pump mounted on the cam galley top of engine (Takes a special "socket" to remove)
The brakes have both systems to power them
The front brakes have two (2) calipers each (4 brake pads per wheel) These are no different than normal calipers to service only they have special "W" springs (one each caliper) to remove and install. Horizontal pins hold the pads in.
The rear brakes have one caliper per wheel but four pistons in each caliper. Still nothing difficult to change.
Here's how they work-
The pumps supply the pressure to make the brakes work BUT the pedal doesn't actually "compress" the fluid it only acts as a valve to allow the pump pressure to go to the brakes (variable pressure by how far the pedal is pushed)
If one or the other pump fails (red panel light on) the other pump supplies enough pressure to make the brakes work.

If both pumps fail (engine dies while driving) of course no hyd pumps are working so no pressure from them to work the brakes.
In this case we have two "accumulators (spherical chamber with a rubber diaphragm with air pressure on one side and vented to the hydraulic system on the other so that the hyd system pressure opposes the air pressure).
If the hyd system pressure fails then there is enough "air pressure" to push hyd fluid down to the brakes and stop the car.
To check these accumulators one only needs to run the engine for 5 or so minutes to build up hyd pressure then shut the engine off and turn the key to "ON" but don't start the engine. Now see how many times you can press the brake pedal until the low pressure brake panel lights come on. You should get around 20 pushes minimum before the lights come on if the accumulators are good.

The suspension on the Rolls works off of the same hyd pumps but uses a different set of accumulators, These are located just in front of the back wall of the trunk (boot in UK language) one on each side. The brake accumulators are located on the right side of the engine block). The "shocks" on your Rolls are not shocks as we normally see but hyd rams that ride up and down on opposing pressure in the accumulators and ride and ride height is governed by a couple other valves under the car.
Lots of utubes on how to change the accumulators.
Ignition is normal
The tranny is a GM 400 standard stuff
The rear end is a normal pumpkin and easy to service
The engine oil pan can be a struggle to drop and reseal but doable.
Coolant is normal practice (NOT DexCool)
Fuel filter is normal on frame under car
The front "struts" do require a special tool to compress the spring (not a normal spring compressor)
All the maint manuals are available on line for free. Brakes are in the HYD section and the owner's manuals are online also.

Hope this helps you understand a little more of the inner workings of a Rolls.
 

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Discussion Starter · #4 ·
The hydraulic system is the big difference in Rolls and other cars you may be familiar with. Think of it this way-
There ae 2 hyd systems in the car #1 and # 2;
Both systems have their own pump mounted on the cam galley top of engine (Takes a special "socket" to remove)
The brakes have both systems to power them
The front brakes have two (2) calipers each (4 brake pads per wheel) These are no different than normal calipers to service only they have special "W" springs (one each caliper) to remove and install. Horizontal pins hold the pads in.
The rear brakes have one caliper per wheel but four pistons in each caliper. Still nothing difficult to change.
Here's how they work-
The pumps supply the pressure to make the brakes work BUT the pedal doesn't actually "compress" the fluid it only acts as a valve to allow the pump pressure to go to the brakes (variable pressure by how far the pedal is pushed)
If one or the other pump fails (red panel light on) the other pump supplies enough pressure to make the brakes work.

If both pumps fail (engine dies while driving) of course no hyd pumps are working so no pressure from them to work the brakes.
In this case we have two "accumulators (spherical chamber with a rubber diaphragm with air pressure on one side and vented to the hydraulic system on the other so that the hyd system pressure opposes the air pressure).
If the hyd system pressure fails then there is enough "air pressure" to push hyd fluid down to the brakes and stop the car.
To check these accumulators one only needs to run the engine for 5 or so minutes to build up hyd pressure then shut the engine off and turn the key to "ON" but don't start the engine. Now see how many times you can press the brake pedal until the low pressure brake panel lights come on. You should get around 20 pushes minimum before the lights come on if the accumulators are good.

The suspension on the Rolls works off of the same hyd pumps but uses a different set of accumulators, These are located just in front of the back wall of the trunk (boot in UK language) one on each side. The brake accumulators are located on the right side of the engine block). The "shocks" on your Rolls are not shocks as we normally see but hyd rams that ride up and down on opposing pressure in the accumulators and ride and ride height is governed by a couple other valves under the car.
Lots of utubes on how to change the accumulators.
Ignition is normal
The tranny is a GM 400 standard stuff
The rear end is a normal pumpkin and easy to service
The engine oil pan can be a struggle to drop and reseal but doable.
Coolant is normal practice (NOT DexCool)
Fuel filter is normal on frame under car
The front "struts" do require a special tool to compress the spring (not a normal spring compressor)
All the maint manuals are available on line for free. Brakes are in the HYD section and the owner's manuals are online also.

Hope this helps you understand a little more of the inner workings of a Rolls.
I've starting to study up on the differences between the Rolls Royce and what I have previously worked on. I appreciate the useful information. The rear of the car was sagging when I got it. When I lifted id to take a look underneath I noticed both rear shocks are leaking quite a bit. We are installing new plugs tomorrow and hope to hear some sign of life. After sitting for 12 years she may need some new fuel pumps.
 

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After 12 years of sitting with old gas in the fuel system, it won't run.
All the oxidized gas will have to be removed from the fuel system before anything is done.
Expect to disassemble and clean all things in the fuel system, from one end to the other.
Adding fresh fuel isn't going to magically fix things.
Someone who has worked in this field for 30 years should realize this; with any car.
 

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The rear shocks are not really shocks like we think of normally they are hyd rams riding against the suspension accumulators for the "soft ride" . My guess is that the 2 accumulators have failed in the suspension system after sitting for 12 years. They are located on each side of the "boot" fwd wall and can be changed with a chain wrench. Screw them off and screw them on WITH the proper square seal ring. Sometimes some mechanics take a long cold chisel to them to get them broken loose on the threads,
 

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These spheres are a direct copy - under licence - of those in Citroens. There are several posts around the various RR/Bentley/Citroen forums that say that the spheres should only be tightened by hand - not "chainwrenched" or spun down to a hard stop. The seal is provided by the square O-ring forced out onto the metal lips. If you have to use a chisel to undo a sphere it is likely that a round O-ring was used or the square O-ring is twisted. If you are wary about finger-tight spheres try to undo a sphere with pressure in the system. It is still normal to have to use a tool to undo finger-tight spheres. There is a special clamp that grips them perfectly, but access can be difficult. The Accumulators are identical to Citroen accumulators, the suspension spheres are RR-only items. Try Ebay or Citroen suppliers in UK or Europe.

It might help to know tt there is a parallel line of Bentley cars which share 99.9% of their components - they were produced on the same production line.

Alan D.
 
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