On my Silver Shadow I wedge a length of wood between the base of the driver's seat and the brake pedal after placing a towel over the seat to avoid scratching the leather. That holds the brake pedal in place while bleeding. Unlike conventional brake systems you don't need to pump the pedal to bleed, the pedal simply operates a valve when depressed and the fluid flows once there's pressure in the accumulator sphere. If you google "how to flush and bleed your Silver Shadow the easy way" by Brian Vogel you will find the simplest method. I know that your car is a Silver Spur but the theory is more or less the same and the bleeding can be done without having the engine running provided that you have pressure in the accumulator spheres. You may need to briefly start and run the engine a couple of times to rebuild pressure during the bleeding process. I bleed mine one calliper at a time using the easy method and I don't need to open the next bleed nipple prior to closing the previous one. Hope that helps.

 

Also, rule of thumb is start with the furthest bleed nipple on the same system, ie System 1, 2 , etc. Keep your eye on fluid level and do not over tighten the nipples. it is easy to deform them and they will have to be replaced. Nipples should exhibit a smooth cone surface on the sealing surface. If they have a circular ridge they were over tightened. A box wrench or line wrench is recommended over an open end wrench to prevent rounding of the hex.

 

Thanks all of you.

I have read "how to flush and bleed your Silver Shadow the easy way" by Brian Voge, it just tell me to drain the system of all hydraulic fluid by opening the brake and height control ram bleed nipples.
However, it does not tell me whether i can do the bleeding with one nipple at a time or I have to bleed all nipples at a time.
And, if I can do it one by one, the order of the bleeding matters?

Really appreciate your help!

Regards,
Danny

 

If you want to drain the fluid from the system you could open all nipples as stated and simply let gravity take over. Normally you would start the engine and let the pressure build up, foot or block on the pedal (or assistant) to release pressure to the system. Start from the rear and work forward on system 1 and then do system 2 and keep your eye on the reservoir level. Do not over tighten the nipples, you could snap them or deform the sealing area of the tip. Also do not pump the brakes, simply depress the pedal.
I like to use the pressure of the system vs gravity. Less potential for mess and it forces the junk out of the system.

 

After flushing close all bleed nipples, refill the clean reservoir, place a weight on the brake pedal, start the engine and let it run for a few minutes to build up accumulator pressure, switch off the engine, top up the reservoir to the max marks. Bleed 1 nipple at a time starting at the rear brakes. You can bleed system 1 and then system 2 or do both in tandem, I prefer to do one system at a time. Occasionally check the reservoir levels and top up as necessary. The pressure in the spheres should be enough to bleed most of the system but if the sphere pressure becomes depleted you can run the engine again for another couple of minutes to rebuild pressure and then resume bleeding. When all the brakes are bled remove the weight from the brake pedal, recheck the reservoir levels, start the engine and with the engine running then bleed the 2 height control nipples with plenty of weight in the trunk to depress the suspension. Stop the engine and finally bleed the pressure switch, check your levels and top up if necessary, check the brake pedal for a solid feel and if you're happy then take a cautious drive on a quiet road to test the brakes. For safety reasons the gear selector should be placed in park, the selector relay should be removed before you start bleeding as there is a risk that you could accidentally select a gear when placing a weight on the brake pedal or when checking the brake pressure warning lights etc.

 

Thanks for your suggestion.
I will try to do what you have told me, and report back what is the result.
BTW, how do I know if I bleed the hydraulic system successfully or not?

Thanks again.

Regards,
Danny

 

Bleeding is a process of removing air from a closed system. Make sure all air is out and you may have to perform a second bleed after a few road miles for any residual air. Bleeding air will not cure any problems you may have within the system with components.

 

If it is properly bled the pumps should be quieter and there should be no squeaks, groans or knocking noises from the hydraulic components (unless a component is faulty), the brakes should be precise and respond well and the car should come to a quick stop in a straight line if you let go the steering wheel while lightly pressing the pedal, there should be no judder in the pedal. Use transparent bleed hose, the bleed hose should rise from the bleed nipples and then fall into the bleed jar, that way you will see any air bubbles rising towards the high point of the bleed hose and when the bubbles stop rising all the air in that particular pipe line should be fully expelled so you can close that bleed nipple and move on to the next one. As Wraithman says it's a good idea to do another quick bleed after a few miles just in case any residual air is still trapped in the system, the air generally tends to find its way to the end of the pipes towards the bleed nipples. It's much easier to bleed if the car is raised on a 4 post lift when access to the bleed nipples is so much easier but it can be done without a lift albeit with more difficult access to the nipples.

 

I have a super dumb question: Which idiot light is for system 1 and which is for system 2?

 

Have the manual?

 

Yes.

 

How to Bleed & Flush Your SZ Series Brakes/Hydraulics Easily