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Nipple Issues
woodstock - 20/2/14 at 09:39 PM

I need some help with my nipples :-)

Puns aside (I've run out), I have just been checking the car over and getting it ready for the year, as part of this I wanted to bleed the brakes. My front calipers are HiSpec Ultralite 4's which have a bleed nipple on the inside and outside of each caliper.

I've not bled dual nipple calipers before but assumed with my single bleed kit I would run fresh fluid through the system to outside part of the caliper and then let a little bit more through on the inside to replace the fluid in that side of the caliper. So firstly, would this be ok or should I really be using a dual bleed system? I did debate making up a 'Y' join in the bleed hose so it connects to both sides but i'm not sure i need to.

Secondly, I've found that one of my nipples is broken.
Nipple Issue
Nipple Issue


This looks tricky to get out as it's only skinny and I could easily damage the thread. Does anyone have any ideas on the best way to approach this?

And do i need to? Maybe I just leave it, It's the inside meaning that as the fluid flows through the caliper to the outside there is bound to be some circulation in the inside edge.

Any advice would be appreciated. This is a track only car so I don't want to take any risks especially when it comes to brakes.

Thanks

Chris


MP3C - 20/2/14 at 09:49 PM

I was curious but also hesitant when clicking this


Matt


woodstock - 20/2/14 at 10:11 PM

I knew there would be a few curious views of this one :-)

I'm thinking that this may be a good option, any thoughts?

Left Hand Spiral Drill Bit Set - *Pack of 4* - Sizes 3mm to 6mm


britishtrident - 20/2/14 at 10:29 PM

If you push the pistons fully back with the nipple open and a bleed tube on you will get most of the fluid out the callipers, close the nipples and get as much fluid out of the reservoir as possible with a syringe or turkey baster.
Top-up with fresh fluid and bleed through.
This will get virtually all the moisture content out the system


nick205 - 20/2/14 at 10:54 PM

Not the thread I hoped it might be


woodstock - 20/2/14 at 11:06 PM

Thanks for the advice. Pushing the piston back will make a massive difference.

Cheers

Sorry to dissapoint those expecting a differnt type of nipple


theprisioner - 21/2/14 at 10:15 AM

If you wanted to take the remains of the nipple try a good quality bolt extractor similar to ebay:201014028865 they come in all sorts of sizes:

http://stores.ebay.co.uk/apmotorstoreoutlet/Tools-DIY-/_i.html?_nkw=extractor&submit=Search&_fsub=11063215018&_sid=1181771348

If you use a cheap one it will make things worse. You may have to drill a hole down the centre of the nipple remains, that is the most tricky part. Best of luck!


woodstock - 21/2/14 at 11:22 AM

Thanks for that - I'll work out the size and order one of these later.

Last night I was thinking i'd just leave it in but it would be sods law that it would start to leak or something on a trackday and I wouldn't be able to do anything about it. Plus it would bug me.


strikerbird - 21/2/14 at 04:53 PM

Like the prisioner said don't use a cheap easy out. We steer clear of the small ones at work now, a broken easy out is a pig to remove.

We've also found if the wall thickness of the broken stud/nipple etc is thin, the extractor forces the sides out making it even tighter!

Would be nice if you could remove it though, just be carefull it shouldn't be that tight.


Darek32 - 21/2/14 at 07:30 PM

I had the same trouble but with bigger bolt which is better to drill and it was in the gearbox ( alu ) no brake ligquid is leaking

Drilled bolt




Extractor





Qoute Strikerbird:

"We've also found if the wall thickness of the broken stud/nipple etc is thin, the extractor forces the sides out making it even tighter!"

I agree with that.
Drilled bolt or that thing u need to extract must have thick wall left after drilled otherwise it will stuck to thread.

it is good to warm it up a little with a hand torch flame




Good luck

[Edited on 21/2/14 by Darek32]


rusty nuts - 21/2/14 at 07:34 PM

It looks as if the nipple has broken off flush with the caliper body in which case Mig welding a nut onto the remains of the nipple would allow you to use a spanner
If the nut shears off weld on another, the heat will help. Worked on some Porsche calipers for me


strikerbird - 21/2/14 at 08:23 PM

quote:
Originally posted by rusty nuts
It looks as if the nipple has broken off flush with the caliper body in which case Mig welding a nut onto the remains of the nipple would allow you to use a spanner
If the nut shears off weld on another, the heat will help. Worked on some Porsche calipers for me


This is how we remove most broken studs at work, a little fiddly being a small nipple and any grease or oil might effect the first nut you try to weld on but this way is normally the most successful.

Good luck


theprisioner - 22/2/14 at 12:21 AM

rusty nuts:- gives good advice here, depends how confident you are with a MIG welder. Striker Bird also makes a good point. My approach would be in the first instance to grind or turn down a bolt, say a 15mm HT bolt with a 8-10mm thread perhaps and match the broken off nipple in diameter to a point at the end. Drill a small depression in the nipple. Inset the point of the bolt and weld the two together wit a MIG. The logic of rusty nuts is convincing.


AntonUK - 23/2/14 at 11:18 PM

I had a similar issue a few years ago with an alloy calliper. I was recommended to use 'spark erosion' but couldn't find anyone who was willing to have a go.

Eventually had to have it drilled out and re-tapped to the next size up. Worked fine up until the day the calliper burst 'Quite Literally'.

I believe its an issued between the steel nipple and alloy housing. Some calliper manufacturers fit a steel insert to reduce the risk.