Brakes Log Out | Topics | Search
Moderators | Register | Edit Profile

Australian RR Forums » Silver Shadow Series » Threads to 2015 » Brakes « Previous Next »

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Hubert Kelly
Experienced User
Username: h_kelly

Post Number: 30
Registered: 3-2012
Posted on Monday, 10 September, 2012 - 05:20 am:   Edit PostDelete PostView Post/Check IP

Had that sinking feeling this evening after applying the foot pedal. I quickly glanced at the accumulator lights. Brakes are perfect, but for that moment I said ....
Top of pagePrevious messageNext messageBottom of page Link to this message

Jan Forrest
Grand Master
Username: got_one

Post Number: 389
Registered: 1-2008
Posted on Monday, 10 September, 2012 - 08:32 pm:   Edit PostDelete PostView Post/Check IP

Used to have the same effect on me until I got acustomed to the momentary delay between pressing the brake pedal and pressure appearing at the calipers.
Still do if some dizzy prat suddenly decides to do something stupid directly in front of me and I have to chuck out the anchor!

See my tale of the daft Kraut in Belgium back in '07.
Top of pagePrevious messageNext messageBottom of page Link to this message

Bill Coburn
Moderator
Username: bill_coburn

Post Number: 1434
Registered: 4-2003
Posted on Tuesday, 11 September, 2012 - 12:00 pm:   Edit PostDelete PostView Post/Check IP

Jan/ Something wrong there. If you are having a delay after pedal application, you will most likely have gas in your brake lines. This gets there through the accumulator diaphragms. The cure is to simply bleed the system.
Top of pagePrevious messageNext messageBottom of page Link to this message

Hubert Kelly
Experienced User
Username: h_kelly

Post Number: 31
Registered: 3-2012
Posted on Tuesday, 11 September, 2012 - 06:41 pm:   Edit PostDelete PostView Post/Check IP

Hi Jan, just found the Post from your, Ostend situation. That was a close one indeed, glad to hear the Shadow escaped, with just a mark of paint on the bumper.
hk
Top of pagePrevious messageNext messageBottom of page Link to this message

richard george yeaman
Frequent User
Username: richyrich

Post Number: 56
Registered: 4-2012
Posted on Tuesday, 11 September, 2012 - 07:59 pm:   Edit PostDelete PostView Post/Check IP

Hi all.

Thanks Bill i also have a delay when brakeing,
Thats another job to add to the list might also save on the laundry bill!!

Cheers.

Richard.
Top of pagePrevious messageNext messageBottom of page Link to this message

Jan Forrest
Grand Master
Username: got_one

Post Number: 390
Registered: 1-2008
Posted on Tuesday, 11 September, 2012 - 09:04 pm:   Edit PostDelete PostView Post/Check IP

The delay is only momentary, but can be heart-stoppingly worrying in panic braking situations. It's important to not then press harder on the brake pedal as it's all too easy to lock up the front wheels on anything other then the driest of road surfaces. This is despite the fact that I overhauled the whole braking sytem a couple of years ago. If I have the time before the end of the month I think I'll renew the fluid again.
Top of pagePrevious messageNext messageBottom of page Link to this message

Hubert Kelly
Experienced User
Username: h_kelly

Post Number: 32
Registered: 3-2012
Posted on Tuesday, 11 September, 2012 - 09:50 pm:   Edit PostDelete PostView Post/Check IP

Hi Jan, I use to think bleeding the Shadow's brake system was the most difficult of jobs, until I got a phone call explaining how to do so.I had my shadow up for sale after spending months working on the brakes, only to find I couldn't bleed them.
His explanation (the guy who called when he saw car for sale) made the process very simple. 1.following successful bleeding of low pressure rear caliper. DO the usual stuff charge/ bleed accumulators etc, but the trick , well I didn't know of it.. was/is to use second person or device to apply pedal thus keeping valves open and work ones way around the cars calipers . What I had been doing was bleeding each caliper separately reapplying pedal to bleed each and subsequent caliper.This is the way I found most successful in bleeding the system, I would not recommend anyone else to try same, as one needs to be aware of the dangers of working with a high pressure braking system as per manual. Jan, I have no doubt you are familiar with the process, but I thought it was a good time to part this piece of information on to others.
hk
Top of pagePrevious messageNext messageBottom of page Link to this message

Jan Forrest
Grand Master
Username: got_one

Post Number: 392
Registered: 1-2008
Posted on Tuesday, 11 September, 2012 - 10:22 pm:   Edit PostDelete PostView Post/Check IP

As you say Hubert; I use a one-way bleed pipe and do the rears in the correct order. Depending on year of manufacture this can be top or bottom first. Then it's just the front sets to complete the job.

When replacing the whole fluid this can be a time-consuming job, but at least the ingress of air can only happen if you don't keep a sharp eye on the level of fluid in the reservoirs.
Top of pagePrevious messageNext messageBottom of page Link to this message

Brian Vogel
Frequent User
Username: guyslp

Post Number: 95
Registered: 6-2009
Posted on Wednesday, 12 September, 2012 - 12:14 am:   Edit PostDelete PostView Post/Check IP

I put together these instructions on Flushing & Bleeding the SY Brake/Hydraulic System based upon information Richard Treacy had posted and my own personal experience when I renewed all of my flex hoses in 2009.

It's much simpler than the wildly complicated method outlined in the Workshop Manual and it definitely works. Provided you keep a close eye on the fluid level in the reservoir when running between wheels this makes the task a one person job.

I'm still trying to figure out how one is ever supposed to be able to bleed the height control rams unless you've got a lift (and if it's not a drive-on ramp lift you still have to work the height control valves by hand). There's no way I could ever figure out to do this with the car on the ground.

Brian
Top of pagePrevious messageNext messageBottom of page Link to this message

richard george yeaman
Frequent User
Username: richyrich

Post Number: 57
Registered: 4-2012
Posted on Wednesday, 12 September, 2012 - 01:06 am:   Edit PostDelete PostView Post/Check IP

Hi Brian.

Thank you for posting such a usefull link, thanks also to Mr Treacy for the original advice,
I have saved it in my favourites so i will be able to find it easily.

Cheers.

Richard.
Top of pagePrevious messageNext messageBottom of page Link to this message

Omar M. Shams
Prolific User
Username: omar

Post Number: 282
Registered: 4-2009
Posted on Wednesday, 12 September, 2012 - 05:00 am:   Edit PostDelete PostView Post/Check IP

I was unable to open the link. Maybe its just my computer.
Here is my way of bleeding the system all on my own with 100% guaranteed results:
My partner is a length of transparent tube approximately 15 feet long. I connect the tube to the bleed nipples (one by one) and ensure the other end is in the appropriate hydraulic oil reservoir in the car. I then sit in the car and press the pedal whilst looking at the contents of the tube. After all the nipples are bled, the car's hydraulics perform like a dream. This system also does the height control rams - as you can bounce the car and see the oil returning to the rear reservoir. I also waste very little oil using this method.
As a precaution, I use a new tube every bleeding session and I also flush the first 100ml of oil that comes out of the new tube before I start recirculating back to the reservoir.
Top of pagePrevious messageNext messageBottom of page Link to this message

Hubert Kelly
Experienced User
Username: h_kelly

Post Number: 33
Registered: 3-2012
Posted on Wednesday, 12 September, 2012 - 06:12 am:   Edit PostDelete PostView Post/Check IP

Brain, fair play to ya....When I first stumbled upon this web site, I searched and searched to see if anyone had posted the simple way to bleed the brakes. I was to embarrassed to ask the question as the manual mentions it i great detail.
hk
Top of pagePrevious messageNext messageBottom of page Link to this message

Hubert Kelly
Experienced User
Username: h_kelly

Post Number: 34
Registered: 3-2012
Posted on Wednesday, 12 September, 2012 - 06:33 am:   Edit PostDelete PostView Post/Check IP

PS Brian, I bleed the height control system, with the car on the ground, HAZARDOUS!!!!!!!!!!! HIGHLY DANGEROUS.Thankfully on the 1968 Shadow the bleed nipples are under the sill, in front of the rear wheel(if ya Know what I mean?.) When I had the bleed nipple working freely I kept away from the underside of the car,.. stretched my arm in, using a ring spanner opened and closed(bleed nipple) as appropriate, the car naturally drops when the Rams are being bleed, so a dangerous procedure, NOT TO BE RECOMMENDED (but it had to be done)
Hk
Top of pagePrevious messageNext messageBottom of page Link to this message

Brian Vogel
Frequent User
Username: guyslp

Post Number: 96
Registered: 6-2009
Posted on Wednesday, 12 September, 2012 - 06:46 am:   Edit PostDelete PostView Post/Check IP

Hubert,

Actually, the height control system does not, technically, need to be bled because it will "bleed itself" during normal operation. [You can research this on this forum.]

The big reason to bleed the height control rams is because under "typical" use for most of us with these cars the height control is never engaged. The fluid in those rams can sit there a very, very , very long time and that can really "crap up" the system if/when it gets released.

It seems that is it perfectly possible to put the rear of the car up on jack stands, have the wheels removed, and bleed the rams. You'd have to disconnect the height control valve arms and manipulate them into the "I've got a lot of weight" position manually then bleed them. With the car up in the air and no wheels you had ought to be relatively safe, but others who've "been there, done that" can confirm/deny.

On the Shadow II there's no real access to the ram bleed screws if the car is on the ground.

Brian
Top of pagePrevious messageNext messageBottom of page Link to this message

David Gore
Moderator
Username: david_gore

Post Number: 1139
Registered: 4-2003
Posted on Wednesday, 12 September, 2012 - 08:36 am:   Edit PostDelete PostView Post/Check IP

A word of advice when working on the height control ram bleed screws - make sure you restrain the body of the bleed screw securely before opening the nipple; the mounting of the bleed screw is very flimsy and if the nipple is tight [as they usually are] you can do serious damage to the mounting.
Top of pagePrevious messageNext messageBottom of page Link to this message

Hubert Kelly
Experienced User
Username: h_kelly

Post Number: 35
Registered: 3-2012
Posted on Wednesday, 12 September, 2012 - 06:09 pm:   Edit PostDelete PostView Post/Check IP

Brian,
Why was the bleed screw, of the height ram not placed in the trunk and attached to the actual ram?. Was it because, in the event of a leak, the brake fluid might rot the wheel arch etc?.
Hk
Top of pagePrevious messageNext messageBottom of page Link to this message

Brian Vogel
Frequent User
Username: guyslp

Post Number: 97
Registered: 6-2009
Posted on Thursday, 13 September, 2012 - 06:59 am:   Edit PostDelete PostView Post/Check IP

Hubert,

If you're asking me why Crewe engaged in any of the "boutique engineering" they seem to have loved you're asking the wrong person.

This is one of those insane decisions to place something in the least possibly convenient location as far as gaining access to it to perform its job.

Though DOT3 brake fluid can serve as a very strong paint remover I don't think it can, by itself, cause rust.

Brian
Top of pagePrevious messageNext messageBottom of page Link to this message

Paul Yorke
Grand Master
Username: paul_yorke

Post Number: 856
Registered: 6-2006
Posted on Thursday, 13 September, 2012 - 07:11 am:   Edit PostDelete PostView Post/Check IP

Hubert, because you couldn't press the arm up and watch the fluid spray out everywhere with a gush! :-)

The rear suspension needs bleeding (imho) because you have a large amount of pipework and the rams which are at a 'dead end' part of the system.

Air trapped in there can never get out and the compression and decompression of that air can make all sorts of noises. Also the fluid will become very stale in there.

Either take the arms off and tuck them onto the balls to hold them open(up), or put six bags of cement in the boot. :-)

When bleeding the brakes, apart from the master cylinder, you can just wedge the brake peddle down. Use the extra person to top up the fluid. It is REALLY REALLY important that the fluid does not get low or you will get more air in the system and end up with delays in the brake peddle action.
Top of pagePrevious messageNext messageBottom of page Link to this message

Jan Forrest
Grand Master
Username: got_one

Post Number: 393
Registered: 1-2008
Posted on Thursday, 13 September, 2012 - 07:45 am:   Edit PostDelete PostView Post/Check IP

IIRC the manual implies (if not actually states) that the suspension ram system is recirculating and shouldn't require bleeding unless all the fluid has been allowed to drain out. I allowed all the fluid to drain from my Shadow's braking system a couple of years ago and never bothered to bleed anything other the brakes. I've had no problems with the self-levelling since I boosted the rear springs.
Top of pagePrevious messageNext messageBottom of page Link to this message

Paul Yorke
Grand Master
Username: paul_yorke

Post Number: 857
Registered: 6-2006
Posted on Thursday, 13 September, 2012 - 03:29 pm:   Edit PostDelete PostView Post/Check IP

Hi Jan,

to the height control valve the fluid is recirculating. ie fresh pressurised fluid is fed to the valve. When the rear suspension is loaded and drops the valve opens and fresh fluid is fed into the pipe going to the ram and the fluid in the rams and pipes is pressurised. When the back is then unloaded , some fluid from the ram pipe is allowed back to the reservoir. To the valve the fluid is recirculating. However the flex pipe to the ram, pipe to the ram, the ram, and the pipe to the bleed nipples is a 'dead end' so what is in there stays on there.

Just as the brakes are self bleeding as far as the distribution valves, but the callipers are 'dead ends' and need bleeding. ( I suspect you have air in this potion of your braking system which is giving you the delay in your brakes!).

Locking up the front brakes as you mention is not usual and is probably caused by "over pressing" the brake pedal to compensate for the air being compressed and once compressed the brakes come on with a sudden 'bang' locking up the wheels.

This often happens slowly over time and owners do not realise they are compensating for it by pressing gently on the brakes. If you swap from your normal car to your RR and find the first couple of stops are too harsh until 'you adjust' to the car, chances are your car needs a bleed.

I get cars in which can have a second delay and the owner says it has been like that since purchase and thought they were al like that! Heart stopping indeed.

"I've had no problems with the self-levelling since I boosted the rear springs." How would you know? It's a bit like saying - one has no problems with ones ankles now one is using crutches. :-)

The self-levelling is a real pita (and costly and unnecessary) and can be by-passed but that is not the same as repairing or maintaining it.

I was tempted to make a joke about the brakes being ok now you have the anchor to throw out . . .
Top of pagePrevious messageNext messageBottom of page Link to this message

Hubert Kelly
Experienced User
Username: h_kelly

Post Number: 36
Registered: 3-2012
Posted on Friday, 14 September, 2012 - 04:33 am:   Edit PostDelete PostView Post/Check IP

Hi Paul, the position of the bleed screw is logical, after your explanation, thanks. Your post also reminds me of a time, I reconditioned a height control valve(changed some seals) I lifted the arm attached to the chassis and the ram lifted the car. I did this action several times, but I went one step to far, in lifting the arm quickly I BUSTED the seal of the height control valve.I do see how quickly the fluid flows when valve opens.Thanks for explaining the re circulatory part also, the manual can be confusing .
HK
Top of pagePrevious messageNext messageBottom of page Link to this message

Jan Forrest
Grand Master
Username: got_one

Post Number: 394
Registered: 1-2008
Posted on Friday, 14 September, 2012 - 07:57 pm:   Edit PostDelete PostView Post/Check IP

I should have said that I had no problems with the rear suspension before I raised it apart from the less than gracious ride height. Ride comfort (other than the occasional thump from the bump stops) was never compromised before and even that is eliminated now.

As for the brakes the delay between pressing the pedal and actual braking effort is barely more than subliminal. However I've been driving cars, trucks, buses, etc. for too many decades to not notice such things.
Top of pagePrevious messageNext messageBottom of page Link to this message

Hubert Kelly
Experienced User
Username: h_kelly

Post Number: 38
Registered: 3-2012
Posted on Saturday, 15 September, 2012 - 05:07 am:   Edit PostDelete PostView Post/Check IP

Jan , I know what you mean. One becomes so accustomed to the individual traits of each vehicle , identifying a problem is quiet easy. I see the Late Sir Norman Wisdom's 1974 Shadow has come to the market for sale,18k euro.
hk
Top of pagePrevious messageNext messageBottom of page Link to this message

Jan Forrest
Grand Master
Username: got_one

Post Number: 395
Registered: 1-2008
Posted on Monday, 17 September, 2012 - 07:55 pm:   Edit PostDelete PostView Post/Check IP

The late Sir Jimmy Saville's Cloud recently sold at auction for around GBP26K (32K euros) if memory serves.
Top of pagePrevious messageNext messageBottom of page Link to this message

Hubert Kelly
Experienced User
Username: h_kelly

Post Number: 41
Registered: 3-2012
Posted on Tuesday, 18 September, 2012 - 07:26 pm:   Edit PostDelete PostView Post/Check IP

Like the cloud but love/adore the Phantom VI limousine, from a coach work point of view, my ultimate, dream car. I am surprised how plain the front seats look though.When I win the lottery, ill stay away from a new Rolls and buy a Phantom VI limo.GBP 26k sounds a fair price, I am assuming it was mint.
Top of pagePrevious messageNext messageBottom of page Link to this message

Jan Forrest
Grand Master
Username: got_one

Post Number: 396
Registered: 1-2008
Posted on Tuesday, 18 September, 2012 - 08:10 pm:   Edit PostDelete PostView Post/Check IP

Apart from his gauche bling and enormous cigars the Rolls was his main extravegance, which he kept in cherry condition at all times having bought it from new.