| Author |
Message |
    
whunter
Frequent User
Username: whunter
Post Number: 28
Registered: 10-2003
| | Posted on Monday, 17 November, 2003 - 03:30 pm: |    |
Hello Steve
One cheap item, often overlooked, the hydraulic tank level floats.
Just replaced both the hydraulic tank level floats on a 1978 Silver Wraith 2, they where leaking.
Put a 3000 psi gauge on system #1. & #2.
Before you begin spending money.
Currently helping a friend with 1972 Silver Shadow hydraulic system.
He blamed the master cylinder, replaced, problem still there.
Rebuilt both system pressure sensors on car, problem still there.
Put gauges on system #1. full of air, wrong fill/check procedure was used, bleed system #1., problem still there.
Put gauges on system #2., 2950.LBS, replaced #2 accumulator and rebuilt spool valve, bleed system #2., pump failed during bleed, inspected both pumps, full of green goop, replaced both pumps, bleed system #2., problem gone.
"Concerned over green goop", drained down system pressure, pulled wheels, dismounted each caliper, open the bleed screw and fully retracted the pistons, close the bleed screw and remount the calipers, we flushed a total of 2.5 US gallons of RR 363 through both systems before we could agree the fluid was clear.
Test drive, he almost stood the car on front bumper, he was accustomed to stomping fast and hard to stop.
He loves the system "now".
whunter
RROC, Lake Michigan, Motor and Ohio region.
ASE Master Mechanic
Bloomfield Eurotech
45671 Woodward Avenue
Pontiac, MI 48341
Work Phone 248-334-6400 Fax 248-334-2363
asemastermechanic@juno.com
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Bob UK
Unregistered guest
Posted From: 172.187.54.69
| | Posted on Tuesday, 18 November, 2003 - 03:40 am: | |
for Rogin
Be carefull with the wiring to the micro switches.
On the Shadows the lives and the earths can touch when re-assembling the switch assembley.
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BOB UK
Unregistered guest
Posted From: 172.187.54.69
| | Posted on Tuesday, 18 November, 2003 - 04:09 am: | |
For Bradley.
For the car to be considered roadworthy it must have the correct number of pumps before the lights come on.
Then when the lights come on the car should still have 2 full aplications of the brakes before the brakes are lost.
Government annual tests do not absolve the owner from a duty of care to maintain the vehicle.
The MOT in the UK is the MINIMUM standard and should not be taken as a guarantee that the car is safe.
The MOT is applied to all cars in the same way regardless of make.
So a Morris Minor is tested in the same way as a Shadow.
The tester can only apply the regs in the book and cannot make up new regs to apply to a particular model.
I have tested on behalf of the government many vehicles which pass the regs but are still not up to snuff.
Accumulators.
Should have a nitrogen pressure of 1000 psi to measure this screw in pressure gauge and start engine.
The gauge should immediately show 1000psi which is the nitrogen pressure then pulse to approx 2500 psi which is the cut out pressure of the valve body. |
Stephen Abigail
| | Posted on Sunday, 18 March, 2001 - 02:03 pm: | |
Hello all, can you help?
My Silver Shadow 74 has started to light up the Partial brake failure and Brake pressure fluid level warning lights on the dash facia.
The level appears to be fine as does the brake pedal's feel and brake performance.
Any ideas on how I may check this out?
Steve |
Bill Coburn
| | Posted on Sunday, 18 March, 2001 - 02:06 pm: | |
Highly unlikely I suspect steve. More likely one of your two systems is failing. The feel of the brake pedal has absolutely no bearing on the condition of the brakes. Assuming your reservoir is full (to the indicated levels) take the car for a run for a few miles. When you get home using the brakes as little as possible - if practical pull up with the handbrake. Run the engine at a fast idle for 2 to 3 minutes then switch off.
Turn the ignition on. Check that the warning lights do in fact work (use oil level check button)then start pumping the brake pedal counting the strokes. Note the number of strokes that each system takes to exhaust indicated by the warning light coming on.
Ideally you should have 60 - 90 strokes for each system. You can survive on thirty, any less and you have trouble.
The most likely problem is that the hydraulic accumulators (have a look in your handbook) have lost their charge of nitrogen. Unless this is picked up early and the spheres are re-charged, the hydraulic pumps will force the internal diaphragms into the charging valve recess at the bottom of the accumulator cutting through through the 'rubber' and any residual pressure will certainly be lost.
There is only one solution and that is to remove the accumulators and have them overhauled.
It is possible but not as likely that one of the pumps on the engine has failed but this can only be checked reliably with a pressure gauge. In any case get them attended to since if the accumulators have failed the only worthwhile braking you have is what the pumps are producing. If the engine stalls you have no brakes and it is very hard on the shoes sticking your feet through the floor trying to pull up! |
Steve
| | Posted on Sunday, 18 March, 2001 - 09:38 pm: | |
Bill's advice is all good but I would add the following.
It should not be necessary to drive the vehicle prior to the test, running for five minutes should be sufficient.
Make sure the vehicle is in "P" and the parking brake appied prior to starting the test because pumping the system down will completely disable the footbrake on most cars. Only earlier Shadow's will retain a very small braking ability as they used an additional master cylinder on one rear brake circuit.
Once the warning lights have illuminated and a note of the number of pumps for each system has been made, continue pumping for an additional 50 strokes. By this stage the system is completely de-pressurised and it is safe to open up any part of it. Start the engine and watch the warning lights, on a correctly operating system they will extinguish immediately. The pump down/start up test is simple, quick and will determine whether the car is safe to use. It is one of the first things a Rolls-Royce trained mechanic will check on an unfamiliar car.
The low pressure warning lights are an essential part of the system and if they ever illuminate when driving it is an indication something is very seriously wrong. There is NO fail safe and if there is insufficient reserve pressure to stop the car the park brake will not help you. You MUST remedy the situation by having the car repaired. If you make repeated brake applications you may deplete what little reserve capacity there is and once this happens the brake pumps may not be able to keep pace with any additional demand. Heavier applications deplete the reserve faster and with a system in very poor condition one pump can illuminate the warning lights. If the warning lamps are not functioning you will never get any indication that a problem even exists until one day you find you cannot stop.
Prior to taking the accumulators and valve bodies off the car its worth getting a dealer to carry out a pressure test. He should only charge half an hours labour and in addition to the state of the nitrogen charge he can also check the function of the accumulator valve assy, the brake pumps and the warning lamp system.
This type of braking system is perfectly safe and has tremendous reserve only if it is maintained in accordance with the manufacturers guidelines by an appropriately trained mechanic. Outside of this it is possible that it will deteriorate to the point where the car becomes positively dangerous to use. Many owners realise when a ball joint is knocking or the shock absorbers need replacing but you be surprised at the number of cars with almost no brakes.
Rolls-Royce shedule an eight year overhaul of the hydraulic system which entails approx 50 hours of labour to renew all the rubber components in the system, renew all the hoses, overhaul the callipers and accumulators as well as a number of other tasks. It can be delayed but not put off forever. |
Bradley Clinch (202.129.95.21)
| | Posted on Thursday, 04 July, 2002 - 11:57 pm: | |
To all concerned.
I have found the information offered here of much interest. Thank you for spending the time to be so helpful to those requesting advice.
I am in the process of buying a 1979 Shadow II, and have had a mechanical inspection of the vehicle by a Rolls Royce experienced and reputable mechanical engineer, which unveiled significant work required on the braking system (besides other areas such as broken differential mounting, engine mount, transmission and steering oil seepage, etc.)
This work was estimated to total about $3000 to $4000- to perform to a suitable standard.
The owner requested a quote for the work required for RWC, and consequently the mechanic supplied him with an itemised list, which included the overhauling of one of the braking systems due to several concerns including soft rear hoses, contamination of one system by a green coloured fluid, and the fact that during the test procedure (as described on this forum) the first warning light illuminated after only 6 light pumps of the pedal (after having first let the car idle for about 15mins after having driven it)
The warning system for the 2nd system is not even functioning, as after a further 100 pumps the light would still not illuminate.
The total of the RWC quote was around $2000.
I now find that the current owner, after having stated that he would have all done to have the car correctly made safe and roadworthy, insists the mechanic only flushes the system and perform the most basic necessities to make the vehicle "roadworthy".
The owner had stated and reiterated that the car has been "meticulously maintained" yet the vehicle has no service records, not even for the period he has owned it (approximately 3 years). The evidence of certain areas having been clearly neglected does not support such a claim.
The car was imported from the UK in 1997, by the previous owner, who I believe had the current owner schedule maintenance on his behalf as part of his employment duties, prior to he then purchasing it himself apparently about 3 years ago.
It appears otherwise in very good condition generally, but this work clearly requires being performed.
The owner also refuses to return my deposit.
Can anyone assist me in where I can obtain (in print) information pertaining to the legal requirements regarding roadworthy standards of this car?
I would be prepared to take the car 'as is' at a reduced cost and rectify these faults at my expense. From my research, I am already paying "top dollar" for a private sale, let alone being expected to also meet these costs.
Thank you in advance for any advice. |
Bill Coburn (203.51.26.121)
| | Posted on Friday, 05 July, 2002 - 05:22 am: | |
Can I suggest that it is a bit unfair to air these problems in this forum. It is here that we try and help owners with mechanical problems not legal ones. Buying any car requires judgement by the buyer with the help usually from someone who knows something about the cars. The roadworthiness of any car is a matter of assessment by the local traffic authorities but there is still considerable onus on the driver/owner to ensure that his car is safe. Clearly this car is NOT safe judging from your description but you have agreed to buy the car as is albeit in good faith. If the seller has no conscience about selling a defective vehicle I suspect only the courts could penalise him. Otherwise, lick your wounds, be a lot wiser and get on with getting the car back up to scratch. |
Rogin (203.213.24.4)
| | Posted on Wednesday, 07 August, 2002 - 09:48 pm: | |
I hope you can help. I have just purchased a 1981 Silver Spirit, It has NO manuel, no paperwork and no instructions.
My left front widow goes down but will not go UP, can you please advise re wireing diagram, location of fuses, or any other information that may be helpful,
Also can you please let me know what the REFUEL button is for ?
Can you tell me what the AUTO FACIA switch is for.?
Any info would be very much appreciated and I look forward to hearing from you.
Rogin Taylor |
Richard Treacy (195.232.90.66)
| | Posted on Thursday, 08 August, 2002 - 08:42 pm: | |
Please see the following about your windows:
http://www.virtualforum.com/forums/Search_Results.cfm?CFApp=12#Message5090
The problem may be a microswitch or a broken wire, but the posting may be useful.
AUTO FACIA: this swaps the air from the bullseye vents on the facia to the demister outlets or vice versa depending on the prelevant status. Push it once and it swaps. Push ita again and it changes back. |
Richard Treacy (195.232.90.66)
| | Posted on Thursday, 08 August, 2002 - 08:45 pm: | |
Oh, and the refuel button opens the electric fuel filler flap. Perhaps you have never needed to fill-er-up-mate ??? |
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