Swammelstein Rolls-Royce

Brake Questions

Question:

I own a 1979 Silver Wraith and am experiencing a "2 Brake Pressure" fault. I have owned this car for about a year and it has been professionally maintained throughout it's life by the previous owner. Both accumulators were changed about 2 years ago addressing the same problem. Recently, I bled the entire braking system, but it only solved this problem temporally.

While doing a visual inspection I noticed that the rubber low pressure reservoir hoses (2 short ones and 2 long ones) all are sweating brake fluld. None of them are broken just a slight amount of fluid along the surfaces of the hoses. The ends are not leaking/all clamps are tight.

Questions: Is this an indication that the hoses must be replaced? Do the replacement hoses have to be the exact RR hoses or will similar automotive type hose work? Could this be the cause of the brake pressure problem?

Last Question: While inspecting, I noticed an unconnected metal line (brake line type) located in the lower front right of the car next to the "reservoir to front pump hose". Any ideas what this is for?

Answer:

Sounds to me like your hoses are wet because the brake reservoir baffles might be missing. also check the condition of the brake reservoir cover screen & 2 cork gaskets. Make sure they have been replace recently & properety torqued. The brake fluid may be splashing around as you are braking & turning corners & leaking from the gaskets. On my cars I am no longer fooling around with the factory cork gaskets. I just use RTV sealer & It does a better sealing job. It also cost less & you can use it for other areas Like thermostat hosing, transmission, oil sump, timing cover & etc. if the brake fluid is constantly exposed to air, you would need to bleed the system more often. Try to keep the reservoir air tight except for the pin holes on the 2 brake fluid cover caps. Buy 2 new round gaskets for the brake filler cover caps from a hardware store. It should cost 15cents ea. If you can't find it buy it then you will have to pay the price from an RR dealer. I believe they will sell it with the gaskets in the caps After 21 years old I am sure it does not do a good seal anymore. One last thing your #2 brake pump rod might be bent. Check it out.

Question:

I have a series I Shadow that the front calipers on the front brakes, will not release unless I open the bleed screws. I have replaced all the rubber hoses and master cylinder, rebuilt all four front calipers. Once I start the car and build up pressure and press the brake pedal the front wheels are locked, and it is only the high pressure calipers that are locking, does anyone know of an bleed off adjustment for these or am I missing somthing?

Answers:

The master cylinder only actuates the rear brakes, one half double caliper each side, and is mainly for feel. The front brakes are operated solely by the accumulators. On later cars the master cylinder was deleted.

The problem doesn't sound serious, just a little patience is needed.

Your problem is almost certainly due simply to a badly adjusted "rat trap", the frame to which the master cylinder and brake actuator valves are fitted, located under the richt hand fron seat. Possibly the master cylinder is badly adjusted causing the brake valves never to close.

I recommend that you follow the setup in the manual.

there are two things to look for, based on what you said you already did. And since you didn't say you messed with the master cylinder and it's the high side only, that rules one of those out.

Take a close look at the distribution valves. They're down under the driver's side seat, just in front of the master cylinder. There are two of them, and they have 3 or 4 pipes going into them. The pedal mechanism has little pins on it that push & release the plungers of these valves.

On my 74, the plungers had stuck, and a good disassembly and cleaning was all that it took. These are a bear to get back in, though, if you aren't real good with brake pipe fittings in tight spaces. You might be able to get them freed up with the valves in place, if they aren't too far gone.

The deal is, it's a closed system, and if the plungers stick, the pressure can't release when you let off the pedal.

Be careful prying on the plungers - they're just finely machined pieces of metal making the seal - no rubber seals. And if you do take them out, be REAL careful keeping track of which pipes go where. The rubber color bands melted right off mine when I slopped brake fluid all over them...

If you had the master cylinder off, or otherwise messed with the adjustment linkage, that'll cause pressure problems too, but in the low side system.