| Author | Message | ||
     Randy Roberson Grand Master Username: wascator Post Number: 761 Registered: 5-2009 |
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... | ||
| Alan Dibley Frequent User Username: alsdibley Post Number: 82 Registered: 10-2009 |
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. | ||
| Brian Vogel Grand Master Username: guyslp Post Number: 2397 Registered: 6-2009 |
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! | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 1489 Registered: 9-2004 |
Could be some of the pads are stuck to the rotors. if all pressure is released from the calipers. | ||
| Randy Roberson Grand Master Username: wascator Post Number: 762 Registered: 5-2009 |
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. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 1491 Registered: 9-2004 |
Imo the rat trap cover needs to be removed to check the linkages are free and retracted. | ||
| ross kowalski Grand Master Username: cdfpw Post Number: 532 Registered: 11-2015 |
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. | ||
| Randy Roberson Grand Master Username: wascator Post Number: 763 Registered: 5-2009 |
Great ideas; will investigate further and report back | ||
| Randy Roberson Grand Master Username: wascator Post Number: 765 Registered: 5-2009 |
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. | ||
| Martin Taylor Frequent User Username: martin_taylor Post Number: 82 Registered: 7-2013 |
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. | ||
| Randy Roberson Grand Master Username: wascator Post Number: 766 Registered: 5-2009 |
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. | ||
| Martin Taylor Frequent User Username: martin_taylor Post Number: 84 Registered: 7-2013 |
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 | ||
| Randy Roberson Grand Master Username: wascator Post Number: 767 Registered: 5-2009 |
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. | ||
| Randy Roberson Grand Master Username: wascator Post Number: 769 Registered: 5-2009 |
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. | ||
| Martin Taylor Frequent User Username: martin_taylor Post Number: 87 Registered: 7-2013 |
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 | ||
| Randy Roberson Grand Master Username: wascator Post Number: 771 Registered: 5-2009 |
Yes, I got them out and apart; the bolt locks were after the struggle and other than brake fluid dripping, not bad. | ||
| h_kelly Prolific User Username: h_kelly Post Number: 225 Registered: 3-2012 |
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?. | ||
| Larry Kavanagh Frequent User Username: shadow_11 Post Number: 97 Registered: 5-2016 |
See "Silver Shadow, flush and bleed you brakes the easy way" for a step by step guide written by Brian Vogel. | ||
| h_kelly Prolific User Username: h_kelly Post Number: 226 Registered: 3-2012 |
Thanks Larry! Thanks Brian also. | ||
| Randy Roberson Grand Master Username: wascator Post Number: 773 Registered: 5-2009 |
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. | ||
| Randy Roberson Grand Master Username: wascator Post Number: 774 Registered: 5-2009 |
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... | ||
| h_kelly Prolific User Username: h_kelly Post Number: 227 Registered: 3-2012 |
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.. | ||
| Geoff Wootton Grand Master Username: dounraey Post Number: 1799 Registered: 5-2012 |
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 | ||
| h_kelly Prolific User Username: h_kelly Post Number: 228 Registered: 3-2012 |
Thanks very much for your advice Geoff, I'll post back later when job complete fingers crossed ACV can/will be saved. | ||
| h_kelly Prolific User Username: h_kelly Post Number: 229 Registered: 3-2012 |
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 | ||
| Geoff Wootton Grand Master Username: dounraey Post Number: 1800 Registered: 5-2012 |
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 | ||
| h_kelly Prolific User Username: h_kelly Post Number: 230 Registered: 3-2012 |
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. |
