MOT Test fail - corroded pipes and brake imbalance :/

[timmaaah 0]

Hi - car went for it's ticket last month and failed, amongst other things, on:

 

Nearside and offside front pipes excessively corroded

Offside rear pipe excessively corroded

Brake load sensing valve seized

Brakes imbalanced across rear axle.

 

Normally I'd give it to a garage to fix, but that's not possible right now. So, a few questions:

 

Are the pipes available off the shelf? If not, how would I get some made up?

The car had brake work done a few years ago, and I seem" to recal them saying they couldn't bleed the front brakes as they couldn't/wouldn't undo the bleed nipples. If the nipples are goosed, is that a problem?

Brake sensor - douse with WD40 and jump up and down in the boot to free it off I assume?

Brake imbalance - looking at the nearside disc, the outer part of the disc isn't being swept by the pad. Faulty pad or sticky calliper? I assume there's meat on the pad as no mention of low pads has been made.

 

It's my only car, so used as and when (although not all that much). Any pointers really appreciated. Thanks

[Kevin Bacon 5]

Looks like a rear caliper for sure on the shopping list, and also a brake proportioning valve if you can't free it off with lube and a hammer. You can probably remove the seized bleed nipples with a set of these - http://www.irwin.com/tools/browse/screw-bolt-extractors/bolt-extractors They do make your life a lot easier when it comes to bleeding.

 

As for brake lines, I redid mine with OEM steel brake line and fittings from the dealer and a decent flaring tool. It's not too bad a job at all and not expensive either. I don't like copper or kunifer pipes, although they are easier to manipulate into shape than steel.

[Dox 23]

My reply copied here from your other thread

You may get away with cleaning up the brake pipes with emery cloth providing they're not too bad, obviously they're a safety related item so this should only be seen as a short term fix, a smear of grease will keep away further corrosion

 

When was the last time the engine was serviced?

 

Rear brake imbalance is likely to be seized pads in the carriers - strip, clean and copper grease the places they touch.

 

The rear brake compensation valve wants spraying with penetration fluid, wire brushing the pivot point, then push / pull on the lever or a tap with a hammer if excessively seized

 

Nipples - wire brush them to excess, dose with penetrating fluid, then lightly tap the ends with a hammer until they begin to distort, more penetrating fluid.

 

Clamp a good set of molegrips to the nipples and rock them gently too and fro, if they don't undo with gentle persuasion go back to the hammer again.

 

Renew the nipples when you get them out.

[Jim 2]

There's a guy here on the forum who makes up complete brake line sets for the VR6. They're very well reviewed / rated from what I understand :) Thread / details can be found here:

 

http://the-corrado.net/showthread.php?53172-Genuine-vw-corrado-brake-lines-remanufactured

[fonzooorooo 10]

If you don't already have them, proper 5 sided brake pipe spanners are an excellent investment! Its so easy to round them off with regular spanners

[timmaaah 0]

Cheers for the advice - I'll see what I can see once I get the old girl up in the air!

[Rich the Chef 10]

Interestingly, mine failed in front brake pile corrosion. So I popped off a wheel and washed/wire brushed/emery papered the pipe and then greased it. Give that it was visually awful. Mud and rust.. The pipe itself was sound and is now fit for mot.

[jekel 10]

I've got two sets of MK4 rear calipers if ya need them, both perfect, rebuilt, new internals, cylinders, seals and handbrake mechs. one with carriers one without, been meaning to stick on Ebay. Also got set of perfect front Audi calipers for 288 mm can fit Corrado with mods, i.e. ya'll need Golf 288 carriers and right pads. (One set red powder coated, not very well, reacted in places, one standard, have had all on my VR6 briefly worked perfect, now upgraded further)

[timmaaah 0]

Ok - had a crack on with this today. The bias valve is ****ed - the rubber bellows is split and some bits dropped out, so a new one will be ordered. It was an utter sod to get off, the bolts seem to go in from the wrong side, and had no heads on the bracket, so the unit had to be ground/hacksawed off -.-

 

Both nipples on the rear are free and easy to turn, and the pistons move in and out on both sides, so I'm going to strip and reseal both the rear callipers, as they seem fine, as do the pistons. The rubber boot on the nearside has totally rotted away though!! A point to note, the flexible pipe that goes over the rollbar/axle/thing? has been rubbing, to the point where I suspect it would fail very soon :/ It's worth checking your pipes ladies and gentlemen. I'll grab a pic next time I'm back at my parents. The corroded offside pipe is the one that runs out of the bias valve and across the axle. I'll make up a new one. The front to rear brake pipes have been refitted in copper at some point, so I'll probably do the replacement the same, or maybe kunifer. The replacement copper ones have been there a while and have done the job.

 

The front nipples. it seems the garage told me a porkie. They've snapped off one nipple -.- I'm going to drill out the old nipple and fit new ones both sides. Didn't get a chance to look at which pipes are corroded as it started raining, but I suspect it's the ones from the pump to the front flexis, which again I'll remake.

 

Onwards and upwards :)

Edited November 28, 2015 by timmaaah