| Author | Message | ||
     Jeff Jones Experienced User Username: jeffoir Post Number: 41 Registered: 5-2007 |
Hi I'm currently restoring an early Bentley S1 and at the moment I'm working on replacing the brake lines. It is the single master cylinder system. I have come across a part (pictured) that appears to be faulty - no air or liquid will pass through it. I also have a Cloud 1 with the same single MC system and it doesn't have this particular attachment. It screws into the 3 way junction located next to the master cylinder. It is attached to the outlet that feeds the rear brake pipes. I have searched all the parts manuals and lists and this part does not appear on them. Does anyone know what this part is and if I actually need this part considering it is not on the Cloud and the Cloud's brakes work well? Many thanks Jeff  | ||
| John Budden Experienced User Username: johnb Post Number: 23 Registered: 4-2006 |
Jeff, It looks to me like a one way valve which consisted of a ball and a spring. Often the spring rusted. It seems a counterproductive device in that context! | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 394 Registered: 6-2006 |
Jeff, you should be able to split and clean it up inside. I believe It's a restictor/valve that stops the master cylinder from sucking the fluid back too fast. It ensures that the master cylinder refills from the reservoir. | ||
| Jeff Jones Experienced User Username: jeffoir Post Number: 42 Registered: 5-2007 |
Thanks for your replies Paul and John. I'll try again to part it, it's proving to be quite seized so John I suspect your prognosis of tyhe rusted spring is right on the ball. Thanks again. | ||
| Colin Silver Frequent User Username: colsilver Post Number: 76 Registered: 8-2008 |
If the spring is rusty, I wonder how long your repair will last. The rust could be made from the metal spring. Have you looked at the spare parts manual available in the library? Look at page F15 onwards. I've had a fairly good look but can't see the valve, which should be next to the T Junction Part # UR.1199 Maybe it was an aftermarket part? Good luck - keep us posted. | ||
| Jeff Jones Experienced User Username: jeffoir Post Number: 43 Registered: 5-2007 |
Thanks for your reply Colin. I'd gone through the parts manuals and couldn't locate it. It's stamped 1956- the car is 1955 so it appears to have been added the year after manufacture. I'll check with Flying Spares and see if they know anything about it and if I actually even need it, considering it's not on the Cloud which has the identical braking system. Thanks. | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 397 Registered: 6-2006 |
I was close   | ||
| John Budden Experienced User Username: johnb Post Number: 24 Registered: 4-2006 |
Jeff, I am tempted by Paul's explanation but perhaps with a variant- is it a sort of anti hammer chamber? | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 398 Registered: 6-2006 |
There, you can be more than temped now Plus you can bin it! LOL. Or just take the insides out and bin them. | ||
| Jeff Jones Experienced User Username: jeffoir Post Number: 44 Registered: 5-2007 |
Paul, thanks very much I appreciate the time you've taken to check that out! I guess I'll just place the seized up old part into file 13....aka the rubbish bin. The car only has 27,000 miles on it and we've been trying to work out if that's correct or if it's been around the clock. The more we look into things it appears it is only 27,000 as we're finding it's 100% all there, and things that sometimes/usually get left off by mechanics over the years are all present. Learning that the brake pipe attachment we're talking about was made obsolete makes me think it even more!! Thanks again... | ||
| Fredrik Selin Unregistered guest Posted From: 91.150.54.254 |
It is the check valve UR2983 "to be fitted with it's non-detatchable end towards master cylinder". See Service Bulletin No. CB.34. (SB/VK.1/RS. 17.12.56). It was an original RR/B modification: time allowance 4 hrs ! (Message approved by david_gore) | ||
| Jeff Jones Experienced User Username: jeffoir Post Number: 45 Registered: 5-2007 |
Thanks Fredrik, I've now found and read the service bulletins related to the check valves. Nice to know why it was there in the first place- mystery solved! I'm glad I don't have to restore the valve- it's all very seized! |
