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Old 15th May 2022, 07:43   #41
SD1too
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Had the master cylinder off the car and even manually pushing the piston it still won't allow fluid out of the rear port.
Hello David,

Are you calling the "rear" port that nearest to the brake servo?

Is fluid being supplied from the other port?

This is important because you've said that fluid is unavailable at all four wheels.

You also said that this fault occurred after your mechanic fitted a new brake pipe. Which one?

Simon
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Old 15th May 2022, 10:02   #42
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Hello David,

Are you calling the "rear" port that nearest to the brake servo?

Is fluid being supplied from the other port?

This is important because you've said that fluid is unavailable at all four wheels.

You also said that this fault occurred after your mechanic fitted a new brake pipe. Which one?

Simon
Simon.--I think fitting of that brake pipe is irrelevant in this case.--If nothing is passing through the master cylinder then there will be no fluid passing through the system at all.

Possibly by just clearing the blockage or by fitting a different ( new ) master cylinder most of the problems will go away.

I think the --Closed Valve---a number have folk have mention is some kind of object blocking the outlet to the master cylinder.

Stripping the original out would provide answers.--- Go, do it now.---
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Old 15th May 2022, 10:08   #43
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Quote:
Originally Posted by SD1too View Post
Hello David,

Are you calling the "rear" port that nearest to the brake servo?

Is fluid being supplied from the other port?

This is important because you've said that fluid is unavailable at all four wheels.

You also said that this fault occurred after your mechanic fitted a new brake pipe. Which one?

Simon

I wonder with the cylinder off the car the piston can be moved fully and smoothly to the full extent of its stroke ?


With the master cylinder full and both ports temporarily plugged it should be easy to see if the master cylinder is at fault, i.e. with both ports plugged it should be impossible to to push the piston to its full travel, if so he needs to look elsewhere.



Whilst plugged, if the piston can be pushed to it's full extent, then it looks like problems at the reservoir to cylinder valve assembly being faulty, in that in normal operation the first few MM of movement of the piston the reservoir is sealed off from the cylinder allowing pressure to be applied to the system, a similar effect an also be caused by faulty piston seals.


How to seal off the ports is quite simple. 2 X brake pipe nuts to suit, 2 X short pieces of copper brake pipe suitably flared ( male or female to suit the port ) at one end and soldered shut at the other end.


There appear to be a few used ones about such as this one.


https://www.ebay.co.uk/itm/275206989...wAAOxy14VRRMlF
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Old 15th May 2022, 10:26   #44
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SO MUCH easier to strip it down than all that fiddling about in the above post.--Go for the easy first---


You know it makes sense.--
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Old 15th May 2022, 11:00   #45
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SO MUCH easier to strip it down than all that fiddling about in the above post.--Go for the easy first---


You know it makes sense.--

That's all well and good if the OP knows exactly how a brake master cylinder works and more to the point, what to look for when he's got it in bits in front of him and how to go about fixing or condemning it !


The fiddling about, as you call it would take at most 30 mins, a miniscule amount of time compared with the hours that have been thrown at it to date.


Making the plugs, there are other ways to plug them a bolt and PTFE tape,
would do and allow, as well as testing his original cyl, allow him to prove say a second hand master cylinder, or a rebuilt one is up to it's job before refitting and finding, that without testing it, the problem still remains.


Yes many go down the ' easy ' path, but as often seen on here and elsewhere, the ' easy ' way, in many instances doesn't result in a fix first time, resulting in more hours wasted.
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Old 15th May 2022, 20:09   #46
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There appear to be a few used ones about such as this one.


https://www.ebay.co.uk/itm/275206989...wAAOxy14VRRMlF
The part fitted to the car is Lucas 3065 so it looks like the ebay item above wouldn't work. After searching the forum the is a thread from a member who has had a similar experience to me ie the part he received is physically incompatible. I've ordered a 3065 (used) from ebay to try. It was under 20 quid including the postage so worth a shot as the chances of it having the same issue are slim.

I've just checked Rimmer bros site and they've changed the description from "all models" to "Except diesel".
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Old 21st May 2022, 12:50   #47
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Took the original master cylinder apart and as suspected the seals had deformed, possibly due to the garage using 40psi to bleed them and not 20psi. It appears that once this has happened you cannot simply reshape and refit the seals as they seem weaker, so the car is having a used MC fitted today.
Fingers crossed.
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Old 21st May 2022, 17:34   #48
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Took the original master cylinder apart and as suspected the seals had deformed, possibly due to the garage using 40psi to bleed them and not 20psi. It appears that once this has happened you cannot simply reshape and refit the seals as they seem weaker, so the car is having a used MC fitted today.
Fingers crossed.
Good news. If the seals were blocking the outlet then fitting new will give you means of stopping now.---


You will no longer be------
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Old 21st May 2022, 17:45   #49
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Good news. If the seals were blocking the outlet then fitting new will give you means of stopping now.---


You will no longer be------
Going for MOT on monday. Car has been off the road for a few months so hopefully no further issues. Then again, with MY luck......lol.
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Old 22nd May 2022, 07:35   #50
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Took the original master cylinder apart and as suspected the seals had deformed, possibly due to the garage using 40psi to bleed them and not 20psi.
Well done Dave and thanks for reporting back. It's shameful that you've been put to all this inconvenience as a result of the garage's actions. I expect you'll be avoiding them in future and I wish you well with the MOT test.

Simon
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