1977 Silver Wraith II Brakes ON Log Out | Topics | Search
Moderators | Register | Edit Profile

Australian RR Forums » Silver Shadow Series » 1977 Silver Wraith II Brakes ON « Previous Next »

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

Randy Roberson
Grand Master
Username: wascator

Post Number: 761
Registered: 5-2009
Posted on Tuesday, 05 September, 2017 - 02:53 am:   Edit PostDelete PostView Post/Check IP

Fellows: now that I have the cranking issue resolved and She runs, She doesn't want to roll.
I confirmed this morning that all four wheels are braked. I bled probably one cup of fluid from the lower bleed port of one of the rear calipers, and I could hear the other calipers release. She's either applying pressure to one of the circuits Herself, or the brakes are not releasing.Hummnnnn...
Top of pagePrevious messageNext messageBottom of page Link to this message

Alan Dibley
Frequent User
Username: alsdibley

Post Number: 82
Registered: 10-2009
Posted on Tuesday, 05 September, 2017 - 03:52 am:   Edit PostDelete PostView Post/Check IP

Brakes not releasing is a sign of elderly hoses which have swollen shut in the brake circuits. The high pressure which applies the brakes squeezes down the restricted tube, but the low pressure of the oil relaxing back into the reservoir just isn't enough.

Because it seems to be both rear wheels(???) it should be possible to get the culprit(s) down to one or two. In my experience, hoses with dimpled surfaces are antiques and should have been replaced with later ones which seem to all have striped ("splined") surfaces.

If you remove a suspect hose and can't blow down it, change the lot.

Alan D.
Top of pagePrevious messageNext messageBottom of page Link to this message

Brian Vogel
Grand Master
Username: guyslp

Post Number: 2397
Registered: 6-2009
Posted on Tuesday, 05 September, 2017 - 04:26 am:   Edit PostDelete PostView Post/Check IP

Second Alan's observation.

The following thread, with my documents related to the braking and hydraulic system on the Shadow series cars, may be helpful:

SY Brakes & Hydraulics - Diagnostics and Maintenance

See also: Silver Shadow Brake Issues: Your Help Would Be Appreciated!
Top of pagePrevious messageNext messageBottom of page Link to this message

Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 1489
Registered: 9-2004
Posted on Tuesday, 05 September, 2017 - 06:10 am:   Edit PostDelete PostView Post/Check IP

Could be some of the pads are stuck to the rotors.
if all pressure is released from the calipers.
Top of pagePrevious messageNext messageBottom of page Link to this message

Randy Roberson
Grand Master
Username: wascator

Post Number: 762
Registered: 5-2009
Posted on Tuesday, 05 September, 2017 - 06:45 am:   Edit PostDelete PostView Post/Check IP

gents, here is the situation now: I can release the Car's brakes by opening bleed ports at all four wheels. I then start the engine and the Car will move about 20 feet then freeze: it is applying the brakes as I drive. Stop the engine, open all the bleed ports again, then I finally got it into the garage.
This is not caused by a brake hose checking due to interior deterioration; it is not caused by pads sticking to the rotors. I never touched the brake pedal during this exercise. It is applying the brakes without command from the pedal, as long as there is pressure in the system.
I will continue to review this Forum and other literature, and the links you kindly provided.
Top of pagePrevious messageNext messageBottom of page Link to this message

Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 1491
Registered: 9-2004
Posted on Tuesday, 05 September, 2017 - 07:01 am:   Edit PostDelete PostView Post/Check IP

Imo the rat trap cover needs to be removed to check the linkages are free and retracted.
Top of pagePrevious messageNext messageBottom of page Link to this message

ross kowalski
Grand Master
Username: cdfpw

Post Number: 532
Registered: 11-2015
Posted on Tuesday, 05 September, 2017 - 07:51 am:   Edit PostDelete PostView Post/Check IP

Randy,

I would pull the rat trap cover as suggested by Patrick L. Not a lot of ways for pressurized fluid to get to that caliper but through the valves in the rat trap.

Either the valve that sends pressure to the caliper is in a position to send pressure because it or it's linkage is frozen or the valve it's self is leaking internally and letting pressure through to the caliper.

Either way, with the rat trap cover off it might be a little clearer whats going on.
Top of pagePrevious messageNext messageBottom of page Link to this message

Randy Roberson
Grand Master
Username: wascator

Post Number: 763
Registered: 5-2009
Posted on Tuesday, 05 September, 2017 - 11:35 am:   Edit PostDelete PostView Post/Check IP

Great ideas; will investigate further and report back
Top of pagePrevious messageNext messageBottom of page Link to this message

Randy Roberson
Grand Master
Username: wascator

Post Number: 765
Registered: 5-2009
Posted on Wednesday, 06 September, 2017 - 08:28 am:   Edit PostDelete PostView Post/Check IP

Removed the rat trap cover this afternoon. All the machinery underneath looks almost pristine: very clean with no signs of rust or binding. Manipulation of the linkage by hand seems it could be no easier. The only anomoly I see is the rubber boots on the distribution valve operating stems seem almost dissolved. There are only minimal signs of leakage of RR 363: no wet fluid but dried yellowish crumbs which are typical.
Top of pagePrevious messageNext messageBottom of page Link to this message

Martin Taylor
Frequent User
Username: martin_taylor

Post Number: 82
Registered: 7-2013
Posted on Wednesday, 06 September, 2017 - 03:35 pm:   Edit PostDelete PostView Post/Check IP

One of your distribution valves must be seized in the open position, if you press on them they should both feel and return the same.
Top of pagePrevious messageNext messageBottom of page Link to this message

Randy Roberson
Grand Master
Username: wascator

Post Number: 766
Registered: 5-2009
Posted on Thursday, 07 September, 2017 - 02:25 am:   Edit PostDelete PostView Post/Check IP

I assumed the movement of the visible polished actuation rod at each valve was positive indication of corresponding movement of the valves' internals. If this is not the case you are probably correct.
If so, what is the recommended course for corrective action? Removal and dismantlement of the valves, swap out, or? They are not inexpensive.
Top of pagePrevious messageNext messageBottom of page Link to this message

Martin Taylor
Frequent User
Username: martin_taylor

Post Number: 84
Registered: 7-2013
Posted on Thursday, 07 September, 2017 - 09:18 pm:   Edit PostDelete PostView Post/Check IP

Test for feel, push each individually, the should feel the same if pressure is the same, it may free up if you can get it to move,
Otherwise remove, dismantle and clean
Top of pagePrevious messageNext messageBottom of page Link to this message

Randy Roberson
Grand Master
Username: wascator

Post Number: 767
Registered: 5-2009
Posted on Thursday, 07 September, 2017 - 09:28 pm:   Edit PostDelete PostView Post/Check IP

After a brief look last evening, I think the top valve may be stuck. After this weekend's family trip is concluded I plan to remove both valves for further examination. This appears to be a simple process.
Top of pagePrevious messageNext messageBottom of page Link to this message

Randy Roberson
Grand Master
Username: wascator

Post Number: 769
Registered: 5-2009
Posted on Monday, 18 September, 2017 - 07:53 am:   Edit PostDelete PostView Post/Check IP

Diagnosis: the ends of the distribution valve which protrude outside the bore seem to be somewhat corroded and sticking in the bores. I figure it is worth a try to clean them up and see what happens, considering the cost of replacements.
Perhaps the fact that the rubber boots were dissolved and no longer protecting the stem areas is the cause. Everything else underneath the aluminum cover was near-pristine. The remainder of the valve interior was perfectly clean as well.
Top of pagePrevious messageNext messageBottom of page Link to this message

Martin Taylor
Frequent User
Username: martin_taylor

Post Number: 87
Registered: 7-2013
Posted on Tuesday, 19 September, 2017 - 06:37 am:   Edit PostDelete PostView Post/Check IP

A bit of steel wool should clean them up, they do have small white plastic seals inside but are actually designed to leak (controlled seepage) to lubricate the valve above the seal.
Lack of use is your most likely cause.
Once removed they are not too difficult to strip apart and clean.
I have some pictures of them apart somewhere
Top of pagePrevious messageNext messageBottom of page Link to this message

Randy Roberson
Grand Master
Username: wascator

Post Number: 771
Registered: 5-2009
Posted on Tuesday, 19 September, 2017 - 06:42 am:   Edit PostDelete PostView Post/Check IP

Yes, I got them out and apart; the bolt locks were after the struggle and other than brake fluid dripping, not bad.
Top of pagePrevious messageNext messageBottom of page Link to this message

h_kelly
Prolific User
Username: h_kelly

Post Number: 225
Registered: 3-2012
Posted on Tuesday, 19 September, 2017 - 07:36 am:   Edit PostDelete PostView Post/Check IP

Hi, quick question can a Shadow 2 brake system be bleed in the same fashion as a shadow 1, ie apply pressure to brake pedal,bleed both accumulators then calipers.
Thanks in advance.
P's have read manual but I'm sure an easier way exists?.
Top of pagePrevious messageNext messageBottom of page Link to this message

Larry Kavanagh
Frequent User
Username: shadow_11

Post Number: 97
Registered: 5-2016
Posted on Tuesday, 19 September, 2017 - 07:58 am:   Edit PostDelete PostView Post/Check IP

See "Silver Shadow, flush and bleed you brakes the easy way" for a step by step guide written by Brian Vogel.
Top of pagePrevious messageNext messageBottom of page Link to this message

h_kelly
Prolific User
Username: h_kelly

Post Number: 226
Registered: 3-2012
Posted on Tuesday, 19 September, 2017 - 12:06 pm:   Edit PostDelete PostView Post/Check IP

Thanks Larry! Thanks Brian also.
Top of pagePrevious messageNext messageBottom of page Link to this message

Randy Roberson
Grand Master
Username: wascator

Post Number: 773
Registered: 5-2009
Posted on Wednesday, 20 September, 2017 - 03:15 am:   Edit PostDelete PostView Post/Check IP

Last evening not more than a bit of clean and polish of the end of the spool valves seemed to restore smooth operation to Her distribution valves. I lubed them with a touch of castor oil and reassembled them easily. Will reinstall as soon as I have time and test them.
Top of pagePrevious messageNext messageBottom of page Link to this message

Randy Roberson
Grand Master
Username: wascator

Post Number: 774
Registered: 5-2009
Posted on Sunday, 24 September, 2017 - 04:52 am:   Edit PostDelete PostView Post/Check IP

Well.. I topped up the fluid and started the Wraith this morning.
First: it started right up, ran a couple of minutes, then died. As if out of gas. I removed the cover of the filter on the A-bank side, poured about 1/2 cup of gas in, replaced the cover, and She started right up and ran perfectly... until that gas was exhausted. I can hear the fuel pump running. I removed it once before because of this same symptom, and found nothing wrong. Hummmnnn....
Back to the brakes: the rear calipers locked again. At least I got the air bled out while I was getting it freed up to roll back into the car barn. Another hummmnnnnn...
Top of pagePrevious messageNext messageBottom of page Link to this message

h_kelly
Prolific User
Username: h_kelly

Post Number: 227
Registered: 3-2012
Posted on Sunday, 24 September, 2017 - 07:01 am:   Edit PostDelete PostView Post/Check IP

Hi all ,question, with the accumulator and valve body removed from the car as one system can they be separated without discharging the nitrogen gas from accumulator. I reckon they can as one can buy a charged sphere separately and fit to valve body?.
Any advice welcomed.
Many thanks
P's new flexible pipes fitted and rear calipers reconditioned to new SS2 , however the bleed screw broke in valve body so to has the draper broken nut removal screw, so I reckon the valve body may be rendered useless..
Top of pagePrevious messageNext messageBottom of page Link to this message

Geoff Wootton
Grand Master
Username: dounraey

Post Number: 1799
Registered: 5-2012
Posted on Sunday, 24 September, 2017 - 01:32 pm:   Edit PostDelete PostView Post/Check IP

Hi Hubert

Yes, they can safely be separated. As you have said, new spheres are delivered fully charged. Be very careful however that both halves of the sphere rotate as a unit. The manual recommends you draw a chalk line across both hemispheres so they can be checked as the ACV is removed. My method was to hold the hemisphere closest to the ACV in my left hand and tap the acv off, in the direction of the screw thread, with a copper mallet.

I hope you can rescue your ACV. Maybe very careful drilling such that the thread is not touched will free it up enough to be able to remove the bleed screw.

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

h_kelly
Prolific User
Username: h_kelly

Post Number: 228
Registered: 3-2012
Posted on Sunday, 24 September, 2017 - 06:18 pm:   Edit PostDelete PostView Post/Check IP

Thanks very much for your advice Geoff, I'll post back later when job complete fingers crossed ACV can/will be saved.
Top of pagePrevious messageNext messageBottom of page Link to this message

h_kelly
Prolific User
Username: h_kelly

Post Number: 229
Registered: 3-2012
Posted on Monday, 25 September, 2017 - 03:21 am:   Edit PostDelete PostView Post/Check IP

Hi Geoff, update for ya.I separated the accumulator and valve body, I had a spare ACV to which I added the original sphere to. All works well presently on short road test.
Thanks very much for your prompt reply.
P's still have the Shadow 1 ,
Thanks again Hk
Top of pagePrevious messageNext messageBottom of page Link to this message

Geoff Wootton
Grand Master
Username: dounraey

Post Number: 1800
Registered: 5-2012
Posted on Monday, 25 September, 2017 - 03:35 am:   Edit PostDelete PostView Post/Check IP

Hi Hubert

Great news that you had a spare ACV and have got back on the road so quickly.

I was curious as to whether you had kept the Shadow 1. I think it's really useful to have two cars as you can be enjoying the one whilst working on the other. My SY1 had recently been laid up for a few weeks and I did miss driving it whilst it was off the road.

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

h_kelly
Prolific User
Username: h_kelly

Post Number: 230
Registered: 3-2012
Posted on Monday, 25 September, 2017 - 04:06 am:   Edit PostDelete PostView Post/Check IP

Geoff,
The original AVE is probably scrap now so I'll probably disassemble same and try become familiar with the rebuilding process if and when the need arises. The shadow 1 is over in my dad's barn for now or till another shed is build here.
Thanks again Geoff it can be a challenge keeping the old cars on the road.

Add Your Message Here
Post:
Bold text Italics Underline Create a hyperlink Insert a clipart image

Username: Posting Information:
This is a public posting area. Enter your username and password if you have an account. Otherwise, enter your full name as your username and leave the password blank. Your e-mail address is optional.
Please quote Chassis Numbers for all vehicles mentioned.
Password:
E-mail:
Options: Enable HTML code in message
Automatically activate URLs in message
Action: