| Author | Message | ||
     Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2501 Registered: 09-2004 |
A short account hopefully. Old age of driver finished the rear pump off(48 years old) hopefully, going deaf or to much volume of Sam Fender to hear what was going on. Any guesses to what really went on causing the failure. Warning light came on and and off circut 2, rear of car would start to drop every time the brakes were used depleting the ram pressure. Returned home with just the two brake systems. Some time spent today removing the Carb assembly but first turn the engine to TDC on front pulley marker. Rotor arm position no 1 on firing stroke. Remove distributor. Getting to the pump first slacken the outlet pressure union for later pump repairs,remove circlip and remove pump housing. First problem housing stuck solid nothing much to hold on to, must not damage it as its made of a thin alloy. Copious amounts of home made penetrating fluid still no go. Next was to fit a set bolt to turn, wow it was able to turn but would not lift (O rings stuck to housing) next was the special ended lever to locate close on the set bolt. With the help of screwdriver well positioned by my grandson it was free.  Enough for today. To-morrow pump removal and hope the push rod is ok. | ||
| Larry Kavanagh Frequent User Username: shadow_11 Post Number: 815 Registered: 05-2016 |
Hi Patrick,For information purposes could you state the thread size of the high pressure outlet aperture on the pump housing? It might be handy to know for future reference, Thanks in advance, Larry | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2502 Registered: 09-2004 |
Larry will have a look to-morrow. BTW, the low pressure is the one question? | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2503 Registered: 09-2004 |
Out of interest thought this would simplifly the firing order 15486372 set up. A bank 1234 B bank 5678 | ||
| Robert J. Sprauer Frequent User Username: wraithman Post Number: 745 Registered: 11-2017 |
It's all in the diagnostics, per gauge attached to the pressure regulator and watching what's going on. Your system was overstresed and either the pressure regulator is not working and most certainly the sphere diaphram is porous releasing fluid back into the system. A pressure gauge would would have indicated if there was pumping pressure going into the sphere in the first place and wouldn't have to pull the pump. | ||
| Robert J. Sprauer Frequent User Username: wraithman Post Number: 746 Registered: 11-2017 |
Also, the pumps are running off the camshaft at half rpm vs the crankshaft rpm, so if you're using straight brake fluid which has no lubrication properties, this will lead to premature wear thru the system. It's a known fact, that's why RR shifted to RR363 vs DOT 3 in the very early cars. | ||
| David Gore Moderator Username: david_gore Post Number: 4061 Registered: 04-2003 |
Robert, This why Castrol added castor oil to the DOT 3 hydraulic fluid to improve its lubrication efficiency in the high pressure Shadow braking system after problems arose with wear from the original RRMC recommendation for straight DOT 3 to be used. This decision would also certainly have been made as a consequence of Castrol's long acquaintance with the use of castor oil as an engine lubricant by motor bike racers. In fact, I would be almost certain the "Cast" in Castrol's company name came from this legacy as "Castrol" is a phonetic version of "castor oil". Another part of the Castrol story would be the experience of First World War pilots who experienced chronic diarrhoea problems from breathing in the oil fumes from the engines where castor oil was also added to the engine oils to improve lubrication.  | ||
| Robert J. Sprauer Frequent User Username: wraithman Post Number: 747 Registered: 11-2017 |
Yes, aware of the shift to 363 with the added lubricant and it's importance. Interesting story, Thanks! | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2504 Registered: 09-2004 |
Sprauer. To bring you up to date. After my mistake causing the pump to fail! Check cracked the the high pressure pipe on top of the pump with engine running Rag used for protection. Not a drop ie pump not working dead. Push rod maybe! Cripes that saved much time and expense if it was a customers car. What you state can be carried out later when the pump is working 'don't fix it if an't broke' comes to mind. My own cars have been running on the better DOT 4 with the recommended mix of castor oil from many year ago by Mr R Treacy. BTW if you use the current makers RR363 it does not need added castor as it is added when produced as your last post implies. Now on with removing the pump. | ||
| Robert J. Sprauer Frequent User Username: wraithman Post Number: 748 Registered: 11-2017 |
Usually the push rod. Even a worn pump will deliver some pressure. Same condition on my first RR 1972. The rod was fractured and there were bits below. Found a small diameter magnetic pick up and all was well. However, there may be a deeper reason the rod went other than old age. It can fracture if it has to forcibly pump against a blockage. Diagnostics is everything. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2505 Registered: 09-2004 |
Diagnostics whether OBD or what is read in manuals it becomes no good if you don’t have procedure this can IMO takes years, and one can still be incorrect at rare times. Bloody hell the pump will not move ‘T’ bar even with 12” extra fitted either side of the T. Time to test the removal tool as a last resort. Out with the impact gun , tightening and undoing still no go. Tool survived so back with the ‘T’ bar with more grunt on extensions now suddenly bang and the pump let go success.   position of correct piston.  Piston not returning points to broken return spring.  Push ok.  New pump fitted  Distibutor fitted  Tells the story  Return valve spring ok. Lunch is ready so that will do for today! | ||
| David Gore Moderator Username: david_gore Post Number: 4062 Registered: 04-2003 |
Patrick, Have opened my memory vault regarding the Shadow brake pumps and I vaguely recollect being told many years ago that the Shadow brake pumps were a CAV diesel fuel injection pump. Perhaps someone can confirm this is correct or it is a case of mistaken identity. Fortunately when I overhauled the hydraulic system on DRH14434, the brake pumps were in perfect condition and the only work required was to replace the original pushrods with the later "waisted" versions as shown in your photo above. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2506 Registered: 09-2004 |
Hum, I seen to recall some talk about them being CAV I think it was the Lister engine, will look later on the genie engines. Shopping to day with the wife, she must be obeyed. | ||
| Martin Webster New User Username: martin_webster Post Number: 26 Registered: 09-2018 |
You are correct David, the brake pumps were originally manufactured by CAV although the patent was held by Citroen. | ||
| David Gore Moderator Username: david_gore Post Number: 4063 Registered: 04-2003 |
Thanks Martin and Patrick, My susceptibility to "Seniors' Moments" must be less than I think.........  | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2508 Registered: 09-2004 |
David don't worry I can remember things from years ago but I seem to suffer with short term memory loss. Martin if memory and my old Citroen's are any-think to go by all Citroen's had rotary pumps mechanically or electrically driven! Back home, so thought I would fit the carb assemblies after removing the material blocking the intake manifold. Forgot to remove the breather pipe connector::: clatter clatter as I lifted the carbs in place. where is it no sign under the car, could it have dropped in the inlet tract. After much checking with the flexi inspection camera decided all was ok. After much searching it had dropped down on the sub frame out of sight by the starter, picture mobile by camera, that's enough for to day.  Free morning tomorrow so will have another go. | ||
| Martin Webster New User Username: martin_webster Post Number: 27 Registered: 09-2018 |
Patrick, if you glance at a copy of the Silver Shadow workshop manual TSD 2476 published in 1968 and probably later amendments, Chapter G, Hydraulics Introduction you will see an acknowledgment that “ Features of the hydraulic control of the brake system licensed by Soc. Anon. Andre Citroen under French Patent Number 1,014,251 and Pat. of Add. Number 61,598. “ R-R re-engineered the system to suit their own requirements paying appropriate dues to Citroen at the same time. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2509 Registered: 09-2004 |
Martin, looks like the pumps were CAV! "The Silver Shadow series started with a hydraulic system that was designed by the French and reengineered by the English. Need I say more? This time around let’s just talk about the brake pumps in this short technical article. The original brake pumps that were fitted to the original cars were heavy industrial diesel injectors that were used on locomotives. They were adapted by CAV, a company that Lucas owned." | ||
| Martin Webster New User Username: martin_webster Post Number: 28 Registered: 09-2018 |
Very interesting Patrick. R-R “ borrowed” heavily from other manufacturers intellectual property via the patent system and redesigned the technology to suit their own requirements.Another example of re-engineering by Rolls-Royce of a French system was the mechanical brake servo which served on all RR products from 1925 to 1965 when the SS was introduced. This was originally designed by Renault, improved by Hispano-Suiza and patented by Royce in 1925. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2510 Registered: 09-2004 |
Martin never new the brake servo originated from Renault. I felt I was never happy with the set up was a devil to get the adjustment right so there was no delay at low speeds. Probably myself not in full understanding of the thing! working correctly they were 100%. To-day fitted the new manifold carb assembly gasket and fitted the carb assembly connected most bits up.    Now the wiring connections all ok except for the LPG, were have I put the instructions from twenty + years ago! Disconnected to isolate the system not thinking about where they go to connect. should have took pictures. New parts so far one gasket one pump and the most brilliantly made pump removal tool from prestige parts.  | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2511 Registered: 09-2004 |
All sorted, nearly. Finished the connections thought I would start up on petrol, waited for the carbs to fill up and un-clipped the choke control so to use full choke flap. Turn the key started and let it idle a few light taps from the new pump. Topped up the brake fluid mix to top level mark, trying DOT 4 semi synthetic, restarted and the rear of car lifted to trim height,sure it was quicker than before. Next test the brake pedal lovely and firm with no warning lights showing. checked the choke control had warmed up and was fully off. Turned the fuel off and ran the car till it faltered and switched over to LPG gas all ok. Time for a short run a little bouncy on the rams with the occasional squawk (never had that before only on the SS2)! Time to bleed the brakes rams etc after letting the systems settle. Noted the occasional different tapping on the old pump when the brakes were applied, maybe this was the pump spring partially broke before the pump gave up. Oh and the final failing of the pump was down to myself driving in intermediate gear at a fair rate of knots. Pump running at 2000 strokes per min. It was only when slowing down with the music load that I thought had a wheel bearing failing, was the viscus fan roaring away. Old age is my excuse.   Engine running OK. Hope this may help. | ||
| Larry Kavanagh Frequent User Username: shadow_11 Post Number: 816 Registered: 05-2016 |
Might be a good idea to clean out and re-seal the 2 restrictor valves while you're at it. A blocked restrictor valve can cause groaning in the height control too. Technically the height control should self bleed but if the low pressure return restrictor valve is blocked the height control can't self bleed back to the reservoir. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2512 Registered: 09-2004 |
Thanks Larry. Will do after a good bleed in case any old fluid and air is still in the system. | ||
| Robert J. Sprauer Frequent User Username: wraithman Post Number: 752 Registered: 11-2017 |
If the car is rising when starting, it's a clear indication the rams are under full time pressure and over worked. Again, the springs provide the standing height. Hopefully you are not using straight DOT4. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2513 Registered: 09-2004 |
To help you "Topped up the brake fluid mix to top level mark, trying DOT 4 semi synthetic" (previous post) This is the castor and mixed DOT4 synthetic I used.    BTW the wood block is used after parking up at trim height + 1/2" when left for days, the rear spring helpers help keep to the trim height. IMO They compensate for the added weight of 90 litres+ LPG tank. Spring asisters are shown somewhere on the forum Another bonus with the wood block when the loaded plant trailer is left connected to the car over night , slip the wood under the tow bar making it much kinder on the springs and rams. Having checked the old pump for wear,so far cannot measure any wear on the pump plunger (piston) Can purchase a spring etc for peanuts so will recon it and keep as a spare for the front pump. No wear confirms OK using the Bake fluid mix over the past years. | ||
| Robert J. Sprauer Frequent User Username: wraithman Post Number: 753 Registered: 11-2017 |
Good move. I use the Cast/DOT mix for years as well. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2516 Registered: 09-2004 |
spring and "0" rings arrived today, time to repair old pump. Cleaned the whole pump parts, years ago in my youth this was carried out with a heated tank of trichlorethylene it stank, I used brake cleaner During assembly the use of brake fluid mix to coat all parts. Pump built up looks good, will it work! I will have to take it to a injector tester when time permits. packaged the pump in air tight bag for long term storage    Early pump picture exploded parts.  . | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2517 Registered: 09-2004 |
Update on the pump replacement job. After the car left standing over night with no support, the next day put the car on the platform lift and bled the brakes and rams. After a good leak down test with the brakes (60+heavy brake pedal pumps, that is enough ) and no warning lights coming on both circuits, gave the car a good run on a bumpy road with no squawks noise from the rams. Retired the car to the garage and left it parked up with no support to the trim height, left for five days weighted, full LPG tank, and checked the height, still at the same as parked. Yesterday gave the car a short 100 mile run big notice was the firmer ride and sharper handling on bends, however the brakes now appear to be more sharper with less feel. Master cylinder and the circuit next to check! One other small annoying thing that has now gone completely is the occasionally heavy tapping from the rear pump on start up or sometimes applying the brake pedal! Wow what a car and cheap to fix DIY. Car now parked with rear support, trim height + ½ inch.  |
