J.R.

If it was an old school 1960's one then they would have been kissing the ground that you stood on, they are allowed to retain & use the old units as long as they are calibrated but if they have to be replaced they can only use a new and approved bluetooth communicating one which costs a fortune to buy and have calibrated. As a consequence the old ones are worth a fortune.

How much does it cost for a main dealer to replace the master cylinder? Having looked back through historic threads on here and other Skoda forums I see a lot of people have had the problem but never found the cause because the dealer had replaced everything either all in one go or on a parts bingo basis, master cylinder, bleed block, slave cylinder but also rushing them for a new clutch and dual mass flywheel for the latter. That amounts to a hell of a lot of money

True. A standard jack on a solid non wobbly support is no more unstable because of the height. There is one problem though, if you use the highest spacer & then try to lift the weight of the car with the jack near to its closed position the geometry will overload it and at that point you will find out why the acme threaded nut is plastic with two shear lugs, very early VAG versions from the 80's & 90's used a metal nut and the side frame would deform releasing it under overload. You get plenty of warning that you are overloading it as you really have to put a lot of force on the crank handle, the higher the jack lifts the less it is stressed. As Sepulchrave has stated its a much safer lift because it can pivot whereas a trolley jack has to roll and often the surface precludes it. The danger with the standard jack is if the vehicle can roll forwards or backwards, an inexperienced person will not realise the need to chock the opposite wheels in both directions, the handbrake may only be working on the side that you are lifting off the ground. Needless to say a flat level firm surface is the safest.

Is it only the 4x4's that have the 6 speed gearbox with concentric clutch and more importantly the clutch torque limiter (bleed block)? Or perhaps the non 4x4's have a bleed block without the torque limiter built in? The so called "torque limiter" slows down the rate at which the clutch is released so that if you do a drag start it will slip rather than risk damaging the driven plate or the drivetrain, you may have on occasions had to drive out of a junction sharpish to avoid oncoming traffic, you knew you had 4x4 so no chance of wheelspin but noticed clutch slip and thought your clutch was on its last legs, it wasn't it was the stupid torque limiter coming into play.

My problems started when I was doing fast gearchanges during full throttle runs testing the results after re-mapping during which time the DPF was throwing off loads of heat. They returned with the new cylinder when doing the same thing, then after re-bleeding etc and driving normally it behaved and the problem returned with the warm weather, it is not present today at 5°C. The old one which I cut apart not having then worked out how to release it without an Octopus should still be in my UK workshop, I reckon when I get back to the UK and can check it I will find that I can easily pull the pushrod out of the piston.

I can guarantee that it wont be the slave cylinder if there has been no fluid loss, (Editted in 2022, I was 100% wrong with that comment!!!) I can also tell you how to test it and prove beyind doubt that the slave cylinder is not faulty. (Editted, again in hindsight that is 100% incorrect as you will see at the end of the thread) Remove the air filter housing to access the clutch bleed block, have someone depress the clutch pedal and put a hose clamp or mole grip onto the flexible pipe leading to the bleed block, this will block the clutch fully disengaged. Leave it overnight and then try to push the car in gear, if the car moves the clutch is still disengaged and there will have been no fluid loss, you can then confidently rule it out and avoid throwing even more money at the garage who is at as much of a loss as you. I have just stripped the 2nd new cylinder again and looked very carefully at the pushrod retainer plastic collet, it is only retained in the piston by a tiny ridge of plastic, no more than a few thou and that is without any wear on the ball joint that articulates, add a bit of heat, some wear, the clutch pedal spring returning the pushrod quicker than the restriction in the bleed block will allow the piston to return and the collet will withdraw partially from the piston meaning it cannot return fully and the bore cannot refill with fluid. If you release the clutch pedal very quickly, sidestep it if you can, if it returns fast with a "clack" when it hits the stop then the pushrod is withdrawing from the piston, it should come up slowly with a damped motion and not impact the pedal stop if all is well, unless the bleed block has been replaced with a full flow performance one. At the moment its a hypothesis but everything points to it, when I fit the second new cylinder where I have glued the collet into the piston (its drying as we speak) then I will know for sure. All 3 of our vehicles are 4x4 but I think that may be co-incidence unless the 4x4's are the only one to have the torque limiter in the bleed block to protect the clutch from drag starts.

That is very helpfull indeed, I am hoping that your memory will be jogged and that you will tell me that it happened in summer. Was your son able to live with it and continue to use the car over several years? I stripped the new master cylinder and may have found a design fault that would cause the problem at higher temperatures, I am going to glue the pushrod retaining collet into the piston as under certain conditions cause by the bleed block restrictor valve it could come out meaning the piston does not return fully which would case the problems I have had. Other cluse are that the new cylinder fitted in the depths of winter did it a couple of times but only when I was doing back to back full acceleration runs on my favorite quiet road test track. The problems only started a week ago with the first of the warmer spring days, the time I turned my central heating off. And today while we are back to freezing weather its fine. Its a long shot but your experience gives me more optimism so thankyou for taking the time to respond.

Anybody? Number 2 master cylinder will be fitted tomorrow unless anyone can put forward any ideas, its a pig of a job and I dont want to do it for nothing. The pedal pumps up and then behaves as normal when driving, leave it for a couple of hours & it drops to the floor with no resistance and does not return despite the really heavy pedal return spring, lift it up, repeat once or twice, pump the pedal and all is well again. Even if you dont drive the car and leave it in constant daytime temperature it will be the same in a couple of hours. I will try giving it another bleed through. The system could not be any simpler, there are no valves or springs in the master cylinder, the piston seal is static in the bore like a brake caliper, the piston is a close fit in the bore and displaces fluid when pushed forwards, when fully retracted it goes back beyond the port allowing fresh fluid to drain down from the brake master cylinder, I have tried loosening the filler in case the vent was blocked. I can't get my head around this problem and those donut type couplings definitely have some purpose and could be the key to this enigma if I knew hat function they performed. Anybody?

The kid is 25 now, a charted architect with children of his own. Bet the poor sod still does not know what a Jumbo box is for!

I don't have one, usually the people that ask that question follow it with "you know what your problem is don't you............."

I think I just might have better things to do than concern myself with a warning light on a video of a second hand car at a main dealers, its not as if they are going to lose any sleep about it is it?

Move to Longford or change the Yeti for a different car

The best way is to trace the cable back from the socket, if you lift the boot carpet you may see it, if its been done in a half decent manner then you wont as it will be tucked behind the rear trim but if you tug back & forth on the exposed part of the cable from the socket to the rear panel you will probably hear whether it goes left ro right & might see something else moving. My money is on it being behind the LHS boot trim, often when the washer pipe freezes and comes apart the fluid goes over the relay and gives it the good news.

Is your aircon not functioning at present?

I am assuming that as its not what many refer to as "dedicated towing electrics" that there will be a multiple relay module triggered by a small control current from the rear lights (it also gives an audible signal when the trailer indicators flash), this will probably be located behind the LH boot side panel, the main feed wire to that will probably have an in line fuse, you will have to tace where it goes, it could be to the rear power socket, to the dashboard fuse box or direct to the battery.

I would first test with a trailer/caravan/trailer board connected, if you have no lights then I would check the live feed and perhaps the earth to the towing socket relay, mine had been hardwired very messily to the battery with some dodgy crimps, not knowing what it was and not being able to trace where this large current wire went to I disconnected it in the hope of finding what did not work, this was on my previous Octavia where the PO had had a so called specialist fit a towbar. It was only when I came to tow and got the same result as yourself it dawned on me what I had disconnected, I reconnected it using proper terminals and a fuse to the a free terminal on underbonnet fuse box bus bar. Somebody may have done the same to your vehicle of the fuse may have blown where shorted trailer wiring has been connected.

Do trailer lights work when they are plugged in? I believe that the 13 pin socket needs 2 pins of the trailer plug to be linked together to create a circuit when its plugged in, are you using a 13 pin tester or a 7 pin one with an adaptor? In either case it would need the 2 contacts linking. Others have said that on the 7 pin dedicated wiring set up the trailer control module detects the resistance of the trailer bulbs, if yours uses that type of sensing then I would not expect a tester to work, they only draw the minimum of currect to light the LEDs and the trailer control module would not be able to sense that one had been plugged in. In many ways I am glad to have simple non dedicated trailer electrics, I dont have reversing sensors etc and my tester works just fine.

Look at the ebay listing for the emulator/simulator for your engine (there is only one real seller) and it will have close up photographs with arrows pointing out all the connections & where the blanking plate goes.

The racer that I had before the Dawes mountain bike was an Emelle!!! I traded it for half of a new but hooky Epson NLQ80 dot matrix printer back when they cost hundreds of pounds. I then had to spend something like £150 on a sheet feeder for it. Been through several printers since then but am very attached to the bike.

I did my first ride since last autumn today on my 30 year old much loved steed (26km) : https://www.retrobike.co.uk/threads/dawes-switchback-etc.240623/ It has 7 speed Shimano STI shifters and mine also finally bit the dust, bits for what are now classed as classic bikes (its the newest bike I ever had & still new to me) are stupidly expensive, I searched the length & breadth of the globe before finally finding what was claimed to be a NOS shifter in a Japanese bike parts shop, for the price with delivery I could have bought a new 28 thousand speed bike from Décathlon but I decided the bike was worth it as we have been round the world together. Its fitted & works fine but I was pretty cross to find it was a second hand unit, mind you they are superbly engineered & I doubt this one has done anywhere near the miles over 3 decades like my failed one had. There is nothing that I can see about a modern bike that would make me want to change unless it was for something a lot more sporting and light.

By the way the diagram shows the external non concentric slave cylinder, mine is the internal concentric one & I think there is one less of those donut things in the hydraulic line.

I posted a couple of months ago that my clutch master cylinder failed on the way home from the engine remap when I was giving it the beans to try the extra power, I limped home & after bleeding had a good pedal feel but it failed soon after on another full throttle run. I replaced it with a VAG part from TPS, the seal had disintegrated on the old one due to its proximity to the DPF and having and using the extra power had finished it off. I then was getting similar problems with the new cylinder under test runs, they were heat related and using VCDS doing just one full throttle acceleration run the DPF temp went above 700°c, I added some rockwool behind the aluminium composite space blanket insulation and stopped the test runs, its been OK since I returned to France but other than the very rare overtake & the regens no real heat has been generated. In the last few hot days it has deteriorated again and it now happens without even driving the car, I get in the car the next morning or even a few hours after parking and the pedal goes half way to the flooe with no resistance & the bite point is very low, despite the huge pedal return spring it will only return half way, I have to hook my foot under it to get it back up, once done the pedal pumps up and it drives OK, last night I pumped it back up & did not start the engine, this morning its the same deal, I think the piston has gone tight in the bore preventing the pedal returning but cant work out why it has the free travel, there is zero fluid loss, the cylinder is a strange type without the internal spring & poppet valve, it has one single pressure seal and also a seal on the pushrod, it fills by gravity from the brake fluid reservoir. I have replaced the clutch bleed block having opened out the retrun flow restrictor valve & thought that might have created the problem, the concentric sleve cylinder is 100% leak free and I have pressure tested it overnight, I thought it may be a high revs crank end float problem pushing fluid back up to the reservoir but have now ruled that out as the problem occurs overnight or within hours without the engine running. I did buy another new cylinder as a spare as I thought I might have problems here where I dont have an equipped workshop. There is only one other possibility and that is there are 2 or 3 odd annular shaped things in the hydrauilic lines which may possibly be accumulators, they are shown on this parts diagram but do not have a seperate part number so there is no description of them, you will see them in each of the clutch lines, they function as a connector elbow but there is absolutely no reason for them to be the massive size that they are, does anyone know what they are and what their function is? Its a pig of a job replacing the master cylinder & even though I am now experienced the job has to be done blind & by feel this is not the place for me to lose the seal, I dont want to do it if the problem might be one of these unidentified things in the clutch fluid line. https://skoda.7zap.com/en/cz/yeti/yet/2015-779/7/721-721030/ Many thanks

Aside from the lease & finance vehicles 90% of what the dealers sell are 3 month old low mileage ex-demonstrator vehicles allegedly driven by the sales manager, they must have an awfull lot of sales managers and of course its nothing to do with them making more profit on a used vehicle sale having reclaimed the VAT on the new vehicle. In 1972 my parents bought a nearly new Ford Capri from the Ford dealership and they were given that line, you would think that after 50 years people might have got wise to it. Everyone that I have known even remotely connected to the car manufacturers or dealers even their daughters at university are given 4 new cars a year that they have to drive for 3 months and put a certain amount of miles on before exchanging for the next one.

I will second that having fitted one as a pre-emptive measure. an excellent product & the guy deserves as much business as we can recommend to him.