38 replies to this topic

[Doodle]

whilst working on my newly acquired metro 4 pots one of the bleed nipples has sheared off when i attempted to remove it, i'm not that overjoyed by it happening but i cant say i wasnt expecting it, how can i remove this bit? i hope its not a drill through and re-tap job, becuase i think the same thing will happen to the other 5...as i planned to replace them all and completely refurb the calipers

i've also got the pistons to remove yet too, which i imagine will be frustrating

[ginigwunkle]

theres load of topics on this,

give it a search and im sure it will pop up several times!

[Doodle]

theres load of topics on this,

give it a search and im sure it will pop up several times!

ahh i didnt realise, cheers

[Doodle]

theres load of topics on this,

give it a search and im sure it will pop up several times!

ahh i didnt realise, cheers

I've had a good search round but cant find anything that helps with dealing with the sheared off bleed nipple, i could try soaking it in WD 40 and using a bolt extractor i guess

has anyone had this happen to them? if so what did you do to fix it?

[nicksuth]

[attachment=50933:easyout5.jpg]

I would first try a stud extractor, also called "easyout", this is very much like a tap but with a left hand spiral thread.
The action of screwing in left handed should start to unscrew the bleed nipple (being right handed).
These are generally used on sheared studs by first drilling a pilot hole to get the easyout started.
Good Luck !

[nicksuth]

[attachment=50934:7c13_1.jpg]

I have just bought a pair of Metro Turbo assemblies to do the same upgrade so if you can give me some feedback when you have completed it all I'd appreciate it?

[ginigwunkle]

on performnace?

they are much better than the std 2pots.

i have a set on mine vith drilled + grooved discs and mintex 1144 pads they are hard to beat!

[minipac]

whilst working on my newly acquired metro 4 pots one of the bleed nipples has sheared off when i attempted to remove it, i'm not that overjoyed by it happening but i cant say i wasnt expecting it, how can i remove this bit? i hope its not a drill through and re-tap job, becuase i think the same thing will happen to the other 5...as i planned to replace them all and completely refurb the calipers

i've also got the pistons to remove yet too, which i imagine will be frustrating

if you go the stud extractor way be careful not to snap the extractor I did this doing the same this and it cost a lot of money to get it out because the stud extractor is made from hardened metal. so these days I take them to my local machine shop with a bit of money and get it done professional. saves time and money

[Doodle]

if you go the stud extractor way be careful not to snap the extractor I did this doing the same this and it cost a lot of money to get it out because the stud extractor is made from hardened metal. so these days I take them to my local machine shop with a bit of money and get it done professional. saves time and money

ah, yeah that is a risk, are you in the west midlands area too? where is your local machine shop?

I've got the other five to remove yet too, i think i'll sock them all in WD40 tonight and see if they shift in the moring

[dklawson]

The only reason I'm posting to this thread rather than encourage you to use the search feature is specifically to counter the "easyout" recommendation above. I detest easyouts and this is one of the worst place to ever consider using them. Suffice it to say, the part has sheared off in a tapped hole and the idea of easyouts is that you drill out most of the remaining part and screw the easyout into what's left to extract it. If you break an easy out (very easy to do with small diameter ones) you're really "screwed". They are hard AND brittle which makes getting a broken easy out the job of machine shops with EDM machines. That equals real money. OK, rant over.

Call local industrial suppliers. Ask them if they carry left-hand drill bits. If anyone laughs, hang-up the phone and try someone else. These are real items, just not very common. Buy a set when you find them. Also buy real penetrating oil, don't resort to WD-40. WD-40 is better than nothing but it is not a real penetrating oil. Soak the caliper/nipple with it, apply a bit of heat, then go away. Come back apply more oil and heat, then go away. Do this for as long as you can stand to wait. Give the oil time to wick into the threads.

Finally fixture the caliper where it is SECURELY held. Clamp it to your bench or something so it can't move. Then, use progressively larger left-hand drill bits to slowly drill into the bleed nipple's bore. GO VERY SLOW. Borrow a variable speed drill if you don't have one. DO NOT drill too deep. Check your depth frequently. Only go as deep as the hole that's already in the nipple. If you're careful and lucky the left-hand drill bit will eventually relieve enough pressure on the threads that what's left of the nipple hangs on the bit and is backed out of the caliper. If not... keep drilling until you start to see the root of the threads breaking through with successively larger bits. Stop at this point and use a hooked probe to remove what's left of the threads.

Avoid re-tapping the caliper if at all possible. The bleed nipple must run very true in its bore for the conical tip to seat and seal. Most of the time when you re-tap the caliper you run the risk that the threads will be slightly larger than when new and the bleed nipple won't seat. If this happens, it's still not the end of the world. A member of this board gave me a method to work around this problem that could be your last resort if you get to this point without success.

If you find the threads in the caliper are badly damaged and that after re-tapping the nipple is loose, buy a new bleed nipple and go to a bearing house to buy a few loose, small steel balls. Find one that covers completely the fluid pilot hole drilled through the bottom of the bleed nipple port. Ideally, this ball will be about 1-1/2 times the diameter of the little pilot hole you'll see. Take your brand new bleed nipple and grind/file it's tip completely away so it has a flat face. Drop the ball into the bleed nipple port and follow it with the flat face nipple. The nipple will push the ball into the seat and close the pilot hole. When you need to bleed the brakes, loosen the nipple as normal and the first application of pressure will unseat the ball so you can bleed as normal.

Again, don't use an easyout. Once they break you'll be off to the machine shop. A friend of mine who used to run a shop said they had a sign up that said something to the effect: "broken bolts removed - $10, ($50 if you've already tried to get it out).

[nicksuth]

Don't forget that you need a reversible drill in order to get the drill bit to cut/drill????

[Doodle]

Thanks Doug, thats immensely helpful

and nick, you get joint second prize with minipac

[minidan]

theres load of topics on this,

give it a search and im sure it will pop up several times!

ahh i didnt realise, cheers

I've had a good search round but cant find anything that helps with dealing with the sheared off bleed nipple, i could try soaking it in WD 40 and using a bolt extractor i guess

has anyone had this happen to them? if so what did you do to fix it?

yes, this exact thing happend to me a few months back. metro four pot calipers, snapped off bleed screw. i took it too an engineering place who quickly told me they wouldnt touch it because they dont want to be responsible for repairing a damaged caliper only to have it fail later on leaving them in the sh!t. fair enough i though and not to put a price on my or my girlfriends life we bought some new 4 pots.

dont muck about with your calipers unless you are a pro.

sometimes its cheaper just to get some more.

[Ethel]

The ball bearing fix is a spot of genius, I'm pretty sure Metty caliper nips are M10x1 the same as the unions so you might even be able to use a male union to hold the ball in.

As for removing pistons - just pump them out using the car's brake hydraulics.

[nicksuth]

Iv'e learnt one thing tonight, there are 3 bleed nipples per caliper on these metro 4 pots = I need to order 2 more!!!! >

PS - mini spares list them as M10 and I think the mini ones are 3/8" ??