CUP172 - REAR BRAKES - ONLY ONE RECEIVING FLUID

[CupRacer172]

I have read a few posts about similar issues but nothing quite what I need advice on.

My car was having new brake lines fitted and when I went to collect they told me only one line at the rear received the fluid. They thought it was possibly the brake valve causing the issue as they rechecked the lines and all were okay, but I arrived when to collect at that point.

My rears discs and pads were only changed in December by my local garage.

I'm drove the car back home (almost 2 hrs) and want to take to my local garage to resolve (they know my car as they did the rear brake discs / oil change etc) however what specifically does this model have different from the later 182's...anything? Has anyone had the experience where one rear line filled with fluid and the other did not?

Any advice is appreciated.

 

[BashRacing]

It’ll be the proportioning valve, euro car parts did stock them

 

[npt]

Spray some wd40 on the valve and work it up and down, most get sticky after a while.
The valve needs to be in the up position to get fluid through the valve, you'll only get a little if the axle is hanging down with car jacked up.
You can tie wrap the valve closed while you bleed it

 

[CupRacer172]

Spray some wd40 on the valve and work it up and down, most get sticky after a while.
The valve needs to be in the up position to get fluid through the valve, you'll only get a little if the axle is hanging down with car jacked up.
You can tie wrap the valve closed while you bleed it

The car had all new rear brake lines. The rsports specialist said they are sure the issue is a blocked valve - to the passenger rear, although the other rear brake was successfully drained.
I've read there's a valve between the wheels but that's all i know at the moment.

 

[16v_paddy]

Spray some wd40 on the valve and work it up and down, most get sticky after a while.
The valve needs to be in the up position to get fluid through the valve, you'll only get a little if the axle is hanging down with car jacked up.
You can tie wrap the valve closed while you bleed it

That only applies to non- Cup though as those are linked to the rear beam, on the 172 Cup that bit isn't connected so the rear braking effort is fixed

The car had all new rear brake lines. The rsports specialist said they are sure the issue is a blocked valve - to the passenger rear, although the other rear brake was successfully drained.
I've read there's a valve between the wheels but that's all i know at the moment.

It's 100% the valve at fault, it might be worth trying to remove the pipes either side of it for the caliper that isn't getting the fluid and blasting it with compressed air on each side to see if it dislodges anything, failing that you'll need a new one. I got mine from Euros but they quite often disappear & reappear in stock there as well as Autodoc which is showing them as in stock https://www.autodoc.co.uk/bosch/671793

 

[npt]

That only applies to non- Cup though as those are linked to the rear beam, on the 172 Cup that bit isn't connected so the rear braking effort is fixed

Yes but the valve sags a little over time on the cup, there's not much can go wrong inside the valve block apart from it getting a little seized, it's very common for them to need some hands on to get them working after a few years, try it, it'll most likely work

 

[CupRacer172]

Would I need to remove the valve to clean it up and what is best to use or should I leave to a mechanic?

 

[npt]

Would I need to remove the valve to clean it up and what is best to use or should I leave to a mechanic?

I just sprayed mine with wd40 and worked it up and down without taking it apart last month, had the same issue you had, worked it a good while and it's back to working fine, they basically never move much which is the issue.
I've had mine coated in wax a few times in the last 10yrs which has helped keep the rust/salt from getting to it, be much easier just fitting an internal bias valve 😂 french sh@t

 

[CupRacer172]

The prices for these has gone way too high, mines in visible good condition no rust, so I will print these tips for the local garage to try and also check the new brakes lines / fluid that were fitted by beaniesport. They also need to refit my exhaust as that was not put back on right after new clamps were fitted by BS (currently hanging down lower than the rear bumper) :/

 

[Matt Cup]

The prices for these has gone way too high, mines in visible good condition no rust, so I will print these tips for the local garage to try and also check the new brakes lines / fluid that were fitted by beaniesport. They also need to refit my exhaust as that was not put back on right after new clamps were fitted by BS (currently hanging down lower than the rear bumper) :/

👀

Oh…

 

[CupRacer172]

UPDATE
My local garage had the car today and confirmed I have to replace the valve - they cannot get fluid through to one rear brake line.

HELP:

I have found a bosch part online however they do not list it being compatible with my CLIO CUP 172 2002 only from 2004 models...

RUK have no stock of the valve.

Who or where can I either get mine repaired (?) or does anyone know of a part or any technical info that can help me use a 182 trophy valve for example (or will that create potential locking rear brakes?


Thanks alot for any tips and advice in advance - I need to keep my CUP going through its 24th year in my ownership

 

[Mr Trailer Man]

UPDATE
My local garage had the car today and confirmed I have to replace the valve - they cannot get fluid through to one rear brake line.

HELP:

I have found a bosch part online however they do not list it being compatible with my CLIO CUP 172 2002 only from 2004 models...

RUK have no stock of the valve.

Who or where can I either get mine repaired (?) or does anyone know of a part or any technical info that can help me use a 182 trophy valve for example (or will that create potential locking rear brakes?


Thanks alot for any tips and advice in advance - I need to keep my CUP going through its 24th year in my ownership

Are they not the same valve, just with the big spring and rod removed?

 

[Matt Cup]

Are they not the same valve, just with the big spring and rod removed?

Mines connected 🤷🏻‍♂️

 

[Mr Trailer Man]

Mines connected 🤷🏻‍♂️

View attachment 1748211View attachment 1748212

Interesting.

Wonder if it's had a new one at some point.

 

[CupRacer172]

I've heard the cup factory fitted are non adjustable which is why they produced a VOSA technical sheet for MOT's.

I'm happy to fit one with a spring although I don't know how Renaultsport changed the rear braking specs for later models 172, 182, 182 trophy etc The only way to check RUK parts is with car reg of those models.

 

[CupRacer172]

update: Renault say those other models (182 etc) do not have load sense valves as they are equipped with ABS

 

[Matt Cup]

This might be a hazy memory but I’m pretty sure I have read on here people have completely bypassed the valve and re-routed some brake pipes back to the m/c.

 

[Matt Cup]

Edit here it is using a brake bias valve but no one concluded the thread.

Can I bypass the...........

......rear brake compensator on my cup ? I know the cup models dont have the compensators connected to the rear beam but its still there. But is the unit its self set at a pre set level ???? . So just wondered if can i just by pass the box with a straight throught lines and would it change...

cliosport.net

 

[Mr Trailer Man]

This might be a hazy memory but I’m pretty sure I have read on here people have completely bypassed the valve and re-routed some brake pipes back to the m/c.

Would need some sort of bias valve.

 

[Matt Cup]

Would need some sort of bias valve.

Yep see above 👍

 

[Mr Trailer Man]

Yep see above 👍

Posted at the same time 😅

 

[16v_paddy]

UPDATE
My local garage had the car today and confirmed I have to replace the valve - they cannot get fluid through to one rear brake line.

HELP:

I have found a bosch part online however they do not list it being compatible with my CLIO CUP 172 2002 only from 2004 models...

This is one of those occasions where the information online is all completely wrong - that Bosch valve is the same part as fitted to other 172's (but not all 172's have it) and the only thing you need to do to make it correct for a Cup is completely remove the rod & spring from it

 

[16v_paddy]

I've heard the cup factory fitted are non adjustable which is why they produced a VOSA technical sheet for MOT's.

I'm happy to fit one with a spring although I don't know how Renaultsport changed the rear braking specs for later models 172, 182, 182 trophy etc The only way to check RUK parts is with car reg of those models.

The "official"-ish term is fixed bias rather than non-adjustable which is because of the Cup not having the valve connected to the rear axle - you can actually adjust the valve itself by undoing the big lock nut and turning the inner thread bit with a 5mm allen key - deffo a bit sketchy to be playing around with it unless you're trying to be really really anal with the setup and got the use of a brake testing machine at an MOT place

 

[CupRacer172]

I've seen some bosch valves on ebay but none match the renault part number for the cup.

Does anyone know if the Bosch can work or be fitted to the cup brake system (or easily modified to work)
as it's over 50% less £

Thanks again

 

[CupRacer172]

Just found a youtube video that includes a brake bias valve being refurbished as the rear of his cup was being stripped and rust proofed.

CLIO CUP BIAS VALVE REFURB

 

[16v_paddy]

I've seen some bosch valves on ebay but none match the renault part number for the cup.

Does anyone know if the Bosch can work or be fitted to the cup brake system (or easily modified to work)
as it's over 50% less £

Renault are absolute arseholes with chopping & changing parts numbers so on anything over 10 years old it's not always a reliable thing to go by.
Another cnut's trick Renault like to pull is having almost completely identical parts with different parts numbers because 1 of them comes with a bolt or something stupid like that - rear discs are a brilliant example of this - I wouldn't be surprised if the bias valves are the exact same parts for 172 and 172 Cup but the Cup 1 has a different part number because it doesn't come with the rod & spring

From when I had the exact same problem on my Cup, as far as I could find out or tell, the Bosch part was the only 1 that existed. I got it from Euro's which just happened to say it fits my car based on the reg but plenty of other places online were saying it's wrong or doesn't fit but that's what I fitted to the car, chucked the rod & spring in the scrap pile and it's all good now.

As bad as this issue is with the Cup braking system, it's at least 10 times worse if you need a servo or master cylinder 😂

 

[Mr Trailer Man]

Yeah i would take a gamble on the Bosch ones with the spring and rod being the same.

Bosch 0204031296 Brake Pressure Regulator

Buy Bosch 0204031296 online. We are Bosch authorised stockists. Free and fast UK delivery.

www.partsinmotion.co.uk

 

[CupRacer172]

Ebay £110 so ordered one