Greetings, All.
I would like to change the brake fluid on SWMBO's ten year old, very neat and tidy, 31k mile 306 1.8 SR Sedan. The fluid has never before been changed in the car's life, and I'm concerned about shearing bleed nipples like I did Donkey's years ago on my MG Metro when the car was only three years old.
Tips and techniques to avoid this, please?
I don't want to start applying heat from a blow torch, or remove the calipers or drum cylinders from the car to work on a bench.
TVM!
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I would give the nipple a short hard shock with the ring spanner , to free it, rather than an increasing torque turn.
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Bleed nipples are a big problem - the big hole in the middle makes them very weak, and they snap off as soon as look at them. I have just overhauled the rear brakes on our 95 ZX, and one of the rear nipples was already sheared and the other was barely distinguishable from sourrounding rust. You may be luckier as yours is low mileage, so mght have spent less time exposed to the road salt, and maybe some time spent garaged. Getting them out without breaking them is still going to be tricky, at best. Start by wire brushing them to get them really clean. Then drown them in plus gas. Leave for a day or two and repeat the plus gas treatment. Do this 4 or 5 times. Now tap gently on the head of the bleed nipple a few times, and then get a short 6 sided tight fitting ring spanner on the nipple and GENTLY tap it with the heel of your hand, first in the tightening direction, then in the undoing direction. It MIGHT come if you are lucky - if not more plus gas and try again in a few days. If you apply steady pressure to the nipple, and it is at all tight it WILL snap off. If this doesn't work then you are going to have to resort to the blow lamp - heat the nipple gently, cool it with plus gas, wait a few moments for the plus gas to evaporate, do this cycle 3 or 4 times, then tap the head of the nipple, then apply the spanner. Heat really is the best way to get the nipples out without breaking them - they should eventually get to the point where they will just unscrew with no force at all - I got the nipples out of the rear callipers on my Xantia this way - and they were very rusty. Patience is the key!
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RichardW
Is it illogical? It must be Citroen....
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Many thanks, both, especially for the nice and detailed assistance RichardW.
I tackle cam belts with aplomb, but I'm not looking forward to this! ;-)
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Best of luck! When I did the rear brakes on our ZX I had to put in new cylinders, shoes, adjusters (some muppet had lost the important bits!), drums, wheel bearings, and pipes.... I mananged to free the bleed screw on one front brake but somebody had already sheared the other one off - fortunately it seems OK.
Rear cylinders are cheap if you do shear a nipple off (although you might end up replacing all as I did!), and nipples can be drilled out of front calipers pretty cheaply. It's probably worth getting a new set of nipples and changing them while you're at it. Apply a THIN smear of copper ease (some folk advise against this in case it 'contaminates' the brake fluid, but I can't see the thinnest smear doing any harm) to the thread to help you get them out next time.
Oh, and invest in a Gunson's Eazibleed - about £15. Lets you pressurise the fluid reservoir, and then just open each bleed screw in turn till the old fluid / air runs out under the air pressure. Dead easy, and no brake pumping required!
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RichardW
Is it illogical? It must be Citroen....
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Never snapped nipples off 306 calipers.....
A short, medium shock with a spanner will usually release them.
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groups.msn.com/honestjohn - Pictures say a thousand words.....
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I very much agree with RichardW about copper paste on the nipple threads. Did this over 5 years ago and they always turn easily. The very thin smeer of grease will not touch the fluid, as with the Easibleed system (a wonderfully easy way to do brakes on your own) the fluid is forced out of the hole one way. Fluid is never sucked back as with a pump/peddle system. If any fluid is on the thread it is compressed in and will not move back and forth from thread to fluid supply. In any case the amounts are very very tiny. If you are going to all this trouble you must get 4 new nipples. Always use a very good, very tight ring spanner, preferably not offset. In my experience, it is also important not to try to do it for the first time without all the wheels off, and you sitting very square to the job. Doing it at arms length stretching will always = rounding off. Interested to know how it goes.
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A word of warning regards the use of a Gunsons easybleed.
Make sure you use the correct seal for the resorvoir on you vehicle, otherwise you will find brake fluid sprayed around the engine bay. Also, when using a wheel to pressurise the system, MAKE SURE YOU DE-PRESSURISE TO 12 psi, its easy to forget and at 30/35 psi, it is likely you will burst apart the fluid resorvoir, as imagined, this could be expensive.
Pastyman....
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Time to come clean.
After the first nipple put up a fight (I did everything recommended except use heat), I lost my bottle and spent £31 (labour, fluid, nipples and VAT), getting my Pug Indy to do it.
Whilst the car was in the air, they performed a pre-MOT (due next month) once over of the running gear and exhaust pipe, too.
What a difference new fluid makes!
Stonking feedback now.
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Glad you got it sorted eventually, I'd have probably done the same after the horror stories I've read here.
I recently did a change on my Escort. If your fluid reservoir looks anything like mine does then I'd flush the fluid out of there. Mine had a horrible gunge at the bottom and took about 4 lots of siphoning to get it all out. I don't know what this gunge is but I'd sooner have it out than in!
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Mike Farrow
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>>I lost my bottle and spent £31(labour, fluid, nipples and VAT), getting my Pug Indy to do it.
With my PUG main dealer charging £25 (all inc.) for a brake fluid change - I'd simply get them to do it because at that sort of price you can't argue. It's like these 'quick oil and filter changes' that the fast fit places seem to be doing. You really can't argue with getting them to do it. Now BMW on the other hand charge £65 for a brake fluid change *GRrR*
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