Hello all,

Got a suspected vacuum leak in the brake system. Wanted to start with the most likely culprit, the vacuum pipe with the inbuilt check valve. Seems impossible to find a replacement. Has anyone managed to find one recently? Or has anyone improvised with vacuum line and a check valve from something else?

Thanks

The difference between ''suspected'' and ''verified'' is huge,don't change parts without approved reason,will cost you a fortune and some parts it's better to leave them ''as is''.

First check the connections,it happened to em in the past and don't get rushed to change parts, in a case with a problem in brake pedal a mechanic suggested to me to buy a new vacuum drum (because he said the original was faulty) and of course a used one because new there isn't any.

I search the whole case by myself,the culprit was a gauge that i had installed in the driver's column supposed to help me in Mpg improving.

There was a leak on it,i remove it together with it's connection hose and problem solved,i saved money and effort (the factory vacuum drum still working as it should be).

Fair comment @D.FYLAKTOS . I decided to buy some money and spend some effort on a 2nd hand smoke machine instead and tested all the intake system and found it to be tight. Worth £25 and an hour of my time. Now I have some more questions but for another thread!

Hello all,

Back to this again, after trying a few other things to fix idle and rev hang issues, I decided to stick a clamp hose on the brake servo vacuum pipe and see if it made much difference and it did. Without the clamp on, if I am sat at idle and pump the brakes, the revs go up. This does not happen when I clamp the pipe. So perhaps this is the cause of my issues. Either a leak in the pipe or the servo itself.

I am going to replace the pipe to start off with. Finding this part now seems to be very difficult. I was planning to just create my own with a vacuum pipe and a non return valve as they are cheap and quickly available. Does anyone have any experience of this? The fitment onto the servo itself looks fiddly.

As you say plenty of vacuum hoses available - DO NOT go cheap Chinese on this and buy from a reputable reliable source, same for valve. Just one possible supplier, check for brake use on pipe and valve, and size of course. - https://www.carbuilder.com/

With the old cars I had a leak in a brake servo could often be seen as white out of exhaust, IIRC. My last old car that I had for 16 years until 3 years ago didn't have a servo so my memories of such are also very old.

ETA: if you have very old (or crap new modern made) rubber hoses be careful of squeezing the hose off as it might deteriorate the hose even more and inside where you can't see might get tiny bits of the hose detaching off and contaminating the system the hose is part of.

I had so much p1ss-poor rubber bits with my last two "classics" going back 20 years that if I couldn't get NOS I'd look for alternatives, for brake flexi-hoses I fitted aeroquip (Goodridge) they were well worth the extra for piece of mind (brakes are the most important thing on a car (tyres are also part of the braking system as well as suspension and steering systems) I had them fitted for almost as long as I had the car and I'd be amazed if they weren't still fitted doing a great job silently, fit 'n' forget (other than visual inspection for other stuff causing them issue of course).

Plenty of Tom, **** and Harrys making up such stuff now but just as an example (for 1.6 Felicia 96-2000). (get D.FYLAKTOS jealous of another old English car company 😁 ).

Goodridge

BRAKE HOSE KIT FOR SKODA FELICIA 1.6 1996-2000 - Goodridge

Performance brake hose kit for Skoda Felicia 1.6 1996-2000. - Goodridge

I have installed Goodridge and EBC parts and i have bought from UK shops plus ebay.co.uk ana amazon.co.uk many products related to car and not only.

No problems at all.

Just winding you up (British banter), I knew it would get you going and I thought you might have fitted aerospec and possibly even Goodridge. I could never understand when there was all the p1ss-poor rubber about why the old farts that owned the "classics" I had would object to fitting them other than the cost but then they were stick-in-the-muds about other items on the car too (modern (proper) synthetic oils) but anything cosmetic was put on the car at whatever silly high price. That made some sense as usually the cars were for show rather than go and rarely ever driven and then not driven as designed for.

Edited 25 March25 Mar by nta16
fat-fingers

Vacuum hose in my 1.3 look a bit weird, it's stiff not soft.

I haven't experience from aftermarket like these:

https://www.llracing.eu/silicone-vacuum-hose-turboworks-pro-12mm-black-mg-rd-024

https://www.ebay.com/itm/236000175771

If my memory is correct good quality vacuum hose from reliable manufacturers will be marked up to show compliance with relevant standards. No doubt you can get cheaper generic but do you want anything cheap on a vehicle's brakes. You can get silicone or rubber. Gates (rubber)is the only name that comes to mind at the moment.

For anyone else considering changing the 6u0611931D pipe and check valve... In the end I used a 12mm check valve from carbuilders along with 1m of 13mm vacuum hose and standard clips:
https://www.carbuilder.com/products/aluminium-non-return-valve-12mm-2

https://www.carbuilder.com/products/heavy-duty-spring-band-hose-clamp

https://www.carbuilder.com/products/vacuum-hose-13mm-id

Worked fine. Removing the line from the booster is a bit fiddly without damaging the connection on the booster. I used a heat gun to warm up the old pipe so I could get it off relatively easily.

Sadly, the issue remains so presume leak is in the booster itself but it was worth trying for the sake of £20 and 30mins of my time.

If you are unsure about brakes then best to sort. The servo itself just reduces the need for working the leg muscles so much but very handy on a light pick-up if carrying weight.

12mm valve on 13mm hose, was it a good tight fit or did you add two clips? Personally I can't stand those self-tightening type of clips and the annoying special pliers you sometimes need to use on them, especially on fit 'n' forget type application (i.e. non-service).