| Author | Message | ||
     Matt stroud Yet to post message Username: stroud234 Post Number: 1 Registered: 10-2018 |
Hi everybody new to the forum and new to owning Rolls-Royce this topic has probably been discussed so many times but can’t quite find right answer on previous discussions just to clarify couple of questions first if I park the car for a night the rear suspension goes down when I start the car the suspension quickly goes up is this normal? Been told it is by rolls-Royce mechanic secondly if I leave the car park for over a week when I started one and two lights come on after the pressure builds they go out should they come on I have got a couple more questions for the group but if someone could answer these two first might help many thanks Matt Stroud from England | ||
| h_kelly Prolific User Username: h_kelly Post Number: 267 Registered: 3-2012 |
Matt, sounds like the height control value has been adjusted in such a way as to compensate for soft springs.ie it sounds like the rear of the car is sitting on the height control rams which are pressurised by engine pump etc..When car sits for a time the pressure drops a thus car sits on soft spring, this expulsion or hydraulic pressure my cause the brake light to illuminate (well one reason they light illuminates) | ||
| Jim Walters Prolific User Username: jim_walters Post Number: 204 Registered: 1-2014 |
Welcome to the forum Matt. The rear suspension sagging is common, it indicates your rear coil springs are weak. The height control activates when the rear end lowers due to extra passengers or luggage. It does the same thing when the springs are weak. When you start the car after a week I would expect to see the brake warning lights come on, then go out after 10 or 15 seconds. They should not come back on when you are driving. You should do the brake pedal pump test to determine the state of the nitrogen charge in the accumulator spheres. Start the engine, let it run for 5 minutes. Shut off. Turn key back to on. Pump brake pedal slowly and count the number of pumps until the first brake warning light illuminates. Continue pumping and counting until the second one comes on. Do this test on flat ground, with the park brake engaged, and block the wheels so there is no chance of the car rolling when the second light illuminates. When both illuminate, you will have NO brakes until you run the engine again. Anywhere from 50 pumps and up the spheres are fine, from 15 to 50 they are partially depleted, less than 15 think about replacing them soon. If you only get 10 pumps or less do not drive the car until you have had the spheres rebuilt and recharged with nitrogen. You can access the factory workshop manuals here: https://rroc.org.au/wiki/index.php?title=Main_Page Click on "Post War Technical" on the left menu then on your model on the next page. Also read through "Tee-One Topics" linked on the main page for relevant DIY articles about Shadow repairs. SRH8505 SRC18015 SRE22493 NAC-05370 www.bristolmotors.com | ||
| Larry Kavanagh Prolific User Username: shadow_11 Post Number: 242 Registered: 5-2016 |
I'm of the same view as H Kelly regarding the height control valve levers being set a little high to compensate for weak rear springs and that the weight of the car on the suspension rams is causing the fluid in the ram to be squeezed back to the reservoir. It's not unusual to hear occasional creaking noises from the rear suspension as it settles down after the car has been parked and the engine has been switched off if the height control has been holding up the rear. Also, if the car has been parked for a week it's not unusual for the pressure to drop which would cause the brake warning lights to illuminate when the ignition is switched on. If the warning lights turn off within a few seconds after starting the engine it suggests that the system is probably pressurising OK. There may be a slight internal leak in a valve or a weep at a connection that's allowing pressure to release slowly when the car is parked over a long period. Check all your pipe connections and bleed nipples for evidence of a slight fluid weep. You can get an idea of the nitrogen pressure in your accumulators if you start the engine and let it run for at least 5 minutes, then turn of the engine and press the brake pedal slowly and hard for as many times as it takes for either pressure warning light to illuminate. You will need the ignition turned on but it's not a good idea to leave it turned on for more than 30 seconds if you have electronic ignition so turn it off and wait a few seconds before turning it on again. If you get more than 30 slow hard pedal presses before a warning light illuminates then that accumulator nitrogen charge is OK, more than 50 pedal presses before it illuminates suggests that the nitrogen charge is good, less than 30 presses indicates that the sphere needs to be recharged, rebuilt or replaced. | ||
| Larry Kavanagh Prolific User Username: shadow_11 Post Number: 243 Registered: 5-2016 |
Sorry, my post crossed with Jim's, follow Jim's advice as it is slightly more detailed. | ||
| Geoff Wootton Grand Master Username: dounraey Post Number: 2045 Registered: 5-2012 |
Hi Matt Welcome to the forum. If you decide to replace the rear springs, it is not a difficult job. It is well documented in the workshop manual and there is also a good article in tee-one topics. | ||
| David Gore Moderator Username: david_gore Post Number: 3031 Registered: 4-2003 |
Hi Matt and welcome to the forum, Further to the link in Jim Walter's post above, you will find the Australian Technical Library has a wide range of technical resources for the Shadow Series plus archive copies of Tee One Topics and Crewe'd Jottings: http://rrtechnical.info/ http://rrtechnical.info/sy/04_sy http://rrtechnical.info/TeeOne/teeone.htm http://rrtechnical.info/CrewedJottings/CrewedJottings.htm  | ||
| Matt stroud New User Username: stroud234 Post Number: 2 Registered: 10-2018 |
Hi guys thanks for your replies to my first questions in regards to the break pedal test have done this and it took over 100 pumps before light came on so I take that the accumulators are fine only asking this because the rear hydraulic pump is ticking quite loudly and you can actually feel the knocking If you hold the top pipe there is fluid at the bottom of the pump which I presume is a leak with this cause the knocking many thanks Matt | ||
| h_kelly Prolific User Username: h_kelly Post Number: 269 Registered: 3-2012 |
Matt, any idea when the brake fluid was last changed?. You probably know only use rr363 castrol brake fluid in a Silver Shadow,it's a special formula to lubricant the hydraulic pumps etc.If you look at the brake reservoir can you see fluid in both glass windows up to proper level?. | ||
| Matt stroud New User Username: stroud234 Post Number: 3 Registered: 10-2018 |
Hi Kelly yes I have put only 363 in reservoir only had the car a couple months when I first picked the car up I didn’t notice the pump making a noise but can’t be sure but after I drove the car couple times I checked the reservoir and the front one was really low may be empty not sure have filled it up since not sure if that caused knocking noise but after driving it quite a few times I have topped it up again that’s why I believe the fluid at the bottom of pump is brake fluid | ||
| h_kelly Prolific User Username: h_kelly Post Number: 270 Registered: 3-2012 |
Hi Matt, if the pump is leaking I'm not there person to advise as it's above my pay grade. However the only thing I can suggest or enquire into is if you bleed the system following top up of rr363 when empty. Did you bleed the accumulator valve body?. Bleeding the brake system is quite specific and I know Brian from the USA has a simple step by step guide on bleeding brakes. If the system needs bleeding the hydraulic brake pump may not be getting fluid, (only air in pump)?. | ||
| Larry Kavanagh Prolific User Username: shadow_11 Post Number: 246 Registered: 5-2016 |
If the fluid is at the bottom only and not at the inlet or outlet pipes there's probably a leak in the lower seal that goes between the pump and the pump housing. There are 2 large seals that go around the pump and when the housing is pushed on over them a seal is created above and below the inlet. It's not a difficult job to remove the pump housing, just open the inlet and outlet pipes and move them aside (you may have to slightly loosen the bottom of the outlet pipe at the accumulator valve to allow the pump end to be moved aside) making sure to plug the inlet pipe or the reservoir will empty fluid all over the place. There's a circlip at the top that needs removal then the housing should pull upwards. Replace both large seals and the smaller seal at the inlet pipe connection. That should cure the leak but the No.2 system will need to be bled afterwards. You wont need to remove the pump. I suspect that the ticking noise from your No.2 pump is caused by air being drawn into the system through one of the large seals between the pump and its housing. When there's air in the system that can be one cause of a ticking pump. | ||
| Matt stroud New User Username: stroud234 Post Number: 4 Registered: 10-2018 |
Hi that’s sound that it could be the problem what dose the rear pump do the brakes or the Suspension or both if it was pumping air Would everything still work | ||
| Matt stroud New User Username: stroud234 Post Number: 5 Registered: 10-2018 |
Hi Larry Just posted last post before I read yours thanks much appreciated that shed a bit of light on the noise thanks very much | ||
| Larry Kavanagh Prolific User Username: shadow_11 Post Number: 247 Registered: 5-2016 |
The No.2 pump at the rear of the engine serves the rear brake callipers on the front hubs, the lower pistons on the rear hub callipers and the height control system for the rear suspension rams. With some air in the system it would probably still work depending on how much air but the brakes would not be as effective and there might be groaning noises from the height control rams and there might be a knocking noise from the pump. The system would be less effective because the air would compress while hydraulic fluid does not compress. Also, air holds moisture and moisture attracts rust and rust creates more problems in the braking system. | ||
| Matt stroud New User Username: stroud234 Post Number: 6 Registered: 10-2018 |
Thanks larry and all the rest on the forum that might suggest the reason why the suspension is going down as well I will try to do the seals on the pump in Near future and let you know how I get on many thanks it good to talk | ||
| h_kelly Prolific User Username: h_kelly Post Number: 271 Registered: 3-2012 |
https://www.google.ie/url?sa=t&source=web&rct=j&url=https://www.youtube.com/watch%3Fv%3D-Y_7a4tUh_U&ved=2ahUKEwi55vzt4aTeAhWHZlAKHZ5lDvoQwqsBMAB6BAgJEAU&usg=AOvVaw3ZzggZjEzkO5KOfRUurMz0 Matt this video may be of help |
