Brake caliper bleeding nipples

[saintjamesy89]

Anyone know the correct size for my GT, front and back? Went to the motor factors today and was given a tray of universal types to routle through. Didn't have a clue which ones I needed so if anyone could shine some light...

Ordered HP pump belt, alternator belt too (apparently there are two sizes??) and rear pads for the hell of it they were only £8.

[Tim Leech]

I imagine they list the alternator/aux drive belt for a car with a/c aswell, even though its rare.

[mat_fenwick]

I would expect them to have a separate entry for vehicles with A/C but I suppose they may not. The only way you'll know for sure is by measuring your old belt with a piece of string/length of wire and seeing which size is nearest. There will be 3 or 4 digits in the belt part no. which correspond to its length in mm, assuming you can't make out any marking on the old belt. Or why not remove old belt and take it along? Decent factors should have a belt length measuring tool.

Bleed nipples on the rear are 8mm across the flats on the ones I've seen. Usually 9mm for the front although I have once seen an 8mm fitted to a recon caliper. I don't think the thread sizes are the same front to back, so the measurement across the flats is not a hard and fast rule. Can you buy one of each size and then return the unused ones? Or again, just remove and bring to the shop? You will barely lose any fluid with a nipple out.

[saintjamesy89]

Thanks chaps, I had planned on measuring the alternator belt as there are of course no visible markings. The bloke did ask if it had a/c so I wonder how many choices there were to start with! Will attempt to take a nipple out from the front and back before returning - they looked pretty rusted in though!

[mds141]

My motor factor asked me the a/c question when I ordered a alternator belt. Re bleed nipples Tom, try your local Citroen dealer. Might still be available and probably not too expensive.

[Dollywobbler]

What's your strategy for the bleed nipples? I'd say there's a fair old chance that the existing ones will be seized into the caliper.

[saintjamesy89]

I've been over two days in a trot and liberally sprayed them with WD40, and I wrote down the socket size for them somewhere to buy the correct hex socket. Hopefully with a bit of gentle cajoling they'll come out.

If they won't come out then i'll see if they will at least do what they're supposed to - bleed! And if not that, then i'll let the MOT man have a go, with the possibility of a recon/new caliper.

[Dollywobbler]

They are dreadful things. The only time I've encountered bleed nipples that come close to matching them for dreadfulness was my Alfa Romeo 164 V6. On which I very easily snapped the bleed nipple off entirely. The ones on my BXs seem to just go round with very little provocation. Hope yours come out!

[Brian]

If you do manage to get them out without drilling.

When you put the new one in, wrap the thread with 3 or 4 turns of PTFE tape.
This will help to isolate the two metals and reduce the corrosion in future.

[MULLEY]

Tom, you'll probably find your hex socket will just round the soft metal that the bleed nipples are made of. This is typical so don't worry when it happens, just stop & use mole grips & like i've said, very gently try & get a little movement when turning & spray plenty of wd40 etc & keep going backwards & forwards until the resistance lestens & they come out You could always try some heat as well, thats been known to help & a good whack with a hammer on the caliper (i also give the bleed nipple a tap as well, not too hard incase it damages the threads), hopefully the shock helps & loosens them from the threads.

[citronut]

dont drive with your nipples out

you cant just go by the spanner size, as the thread pitch and diameter varies quite a bit,
also the length and the angel of the tip/matting surface is important

regards malcolm

[mds141]

Would it be possible to make a spout/funnel from blu-tak or similar. Mould it round the bleed nipple, pour in some light oil or penetrating fluid and let it soak in over a couple of days.

[Mickey taker]

isnt plus gas better for this than WD40, you want a full on Dismantling De-Seizing Lubricant Aerosol not what is primarily a water dispersant one.
plus gas gets in all the little nooks and crannys and helps things slip in and out ( bit like KY jelly Tom )

[hilarystone]

Yes Plus Gas is a much better idea than WD-40 which is simply a water dispersant. And I'd also get some 1/4in flank drive sockets to fit – they won't round the nipples – though the nipples may still break...

[saintjamesy89]

Well after all the prevarication about them, the bloody things came out without so much as a single swear word being employed! I think 2 days of liberal WD40 spraying and a tap with a hammer on the calliper obviously helped. Went back to the motor factors as the belts i'd had on order came in and got the most similar nipples they had.



I know they look different, but the old nipples had thread protruding ou tof the caliper, as in they were too tall so these slightly shorter ones have just about enough thread. But they aren't quite as pointy so we'll see if they leak or not. No LHM came out when I removed these two from the rear callipers btw, but she has been on axle stands for a week or so.

I wonder if the fronts will be so easy?