Corroded brake bleed nipple - best way to extract?

[Andy 308GTB]

I was attempting to flush the brake fluid on my 16 year old Ford Focus.

On the rear drum brakes the bleed nipples are completely shot. I managed to get the offside one bled, using mole grips, as there was nothing left for a spanner to get hold of. But the nearside is really bad (see photo).
Is plenty of Plus Gas and mole grips the best way to remove them? There isn't a lot of room and mole grips are a tight fit. Obviously, I'm nervous of them snapping off.

Edited by Andy 308GTB on Sunday 14th October 19:05

[Andy 308GTB]

E-bmw said:

TBH with a bleed nipple looking like that I would have gone straight for a new slave cylinder.

Either that or buy a new nipple & get the drill out expecting it to shear, which is not always a bad thing.

Thanks.
I'll have to look into fitting a new slave cylinder, not a clue how much work that would be.
But on Ebay they are cheap as chips, which appeals to me!
Where's that Haynes manual...

[Andy 308GTB]

Once I worked out that Slave Cylinders are now referred to as Wheel Cylinders in Videoland, life became a lot easier...

I found this excellent video on YouTube:
https://www.youtube.com/watch?v=1j7qDoi1LP0

It's a bit theoretical because the car they are working on has clearly never been out in the rain or been 'serviced' by a gorilla who thinks that every nut and bolt should be tightened until the threads are ruined. I'd happily eat my dinner off the underneath of their car.
Other videos on the subject of replacing Wheel Cylinders, invariably dwell on rounded off nuts, use of angle grinders and trying to stay calm.

This all feels a bit st or bust.

[Andy 308GTB]

souper said:

Never tried this, but always remembered this method, If rusted and difficult the chances of the nipple loosening are rare as the hollow brake nipple collapses in on itself breaking off. The method was to put either a drill or a rivet point into the nipple hole thus filling in the empty space making the part to be turned out much stronger with a spanner/mole grips, worth a try before drilling.

That's a good tip. The risk of crushing the bleed nipple was one of my concerns when I initiated this thread. It would go from being a routine job to major car surgery.

I am going to order up new bleed nipples all round (£5 on Ebay) and have another go at the weekend. If nothing will budge, I'll see if the nuts holding the wheel cylinders in place can be undone. If so, I'll order a pair of new wheel cylinders (£12 on Ebay) and push it along another week...

[Andy 308GTB]

I replaced the offside rear nipple with a bright, new shiny one, yesterday.
This weekend, I will have a crack at the nearside rear nipple which was a complete mess and wouldn't budge previously. Since I need the car on a daily basis, I am going to work through the many suggestions, starting with the text book ideas before moving down an increasingly destructive path. The ultimate step will be to remove the drum and replace the wheel cylinder (which I have at the ready).

Obviously, I was unable to bleed the front discs because Ford used 9mm bleed nipples. I now have a 9mm spanner (£1.99). What is it with Ford, when i replaced an A-Arm all the bolts were 18mm - I now have about 6 different types of 18mm sockets. All only used once.

I will also replace the Front Pads at the same time because they were wafer thin.

This was meant to be a 15 minute job to flush the brake fluid...

[Andy 308GTB]

I've abandoned any hope of removing the bleed nipple, I was able to hammer on an 8mm spanner but it still wouldn't budge.

I now have a pair of brand new wheels cylinders (£6 a piece on Ebay). But inevitably, as the good Doctor found, the 8mm nuts that hold on the existing wheel cylinder are tricky. Mine are rusted in a similar manner to the bleed nipple - i.e. they are rusted and round off at the slightest touch of a socket.

I've seen a really nasty video on YouTube where somewhere resolved this using an angle grinder on the wheel cylinder itself.
I'm thinking of taking a sharp cold chisel and trying to knock/chop the heads off the 2 bolts? Would this work? If the bolts heads are 8mm they can't be that substantial. I can't get anything else to them, they are tucked out of the way.

I can manage without the car for a day or two but I don't want to end up in a situation that I can't resolve myself. So any solution shouldn't be too ambitious.
And I need to get this done a.s.a.p. as I need to service the wife's car. Then I have a winter project of learning how to rebuild 4 Weber carbs...

Old Merc said:

By the look of the OP`s image the rear end looks as if it came from the deck of the Titanic.

I beg your pardon, I'll have you know the insurance value of the vehicle is £148

[Andy 308GTB]

Thanks chaps.
Getting mole grips or a Dremel onto these bolts isn't possible. An 8mm socket on a universal joint type wrench is about the only way to access them but mine are too corroded.
I did remove the hub spindle assuming the 4 large bolts held the backing plate on. But it didn't budge and I assumed it was welded to the suspension arm. I needed the car so I put it all back together again.

I have subsequently found a video showing that it's held on with 2 rivets! On my next attempt I will drill these out and get it on the bench.

I didn't expect there to be a lot of enthusiasm for my cold chisel idea!