I've tried penetrationing spray, hitting the body of the caliper near the bleed nipple to shock it, wire brushing exposed thread, hitting spanner in direction to undo to add repeated shocks. Turning slightly in tightening direction. Tried using a socket. I note that 11mm seems loose but 10mm won't fit.

 

What next? Blow torch? Just go for it and be prepared to buy a new caliper? (I'm thinking new calipers might be best anyway given they're nearly 20 years old.)

 

Thanks in advance.

Edited 1 April, 20215 yr by anewman

 While you say penetrating fluid, is this a good brand or "WD-40". I have found that PlusGas gives much better results that WD. One method is to carefully apply heat on the bleed nipple and surrounding area, I use a pen type torch which give a smaller localised flame area, and when hot apply penetrating fluid which may be drawn into the threaded area or even give expansion/contraction at the thread interface. What you must not do is apply so much heat that any seals are effected or the brake fluid is boiled as if it doesn't work you will probably have to drive it again.

8 hours ago, KeithCheetham said:

 While you say penetrating fluid, is this a good brand or "WD-40".

It's Halfords release spray. Says it contains naphtha (petroleum). I've seen Screwfix sell plusgas but the postage cost on top is pricey.

 

Persevered a little more and got it to undo in the end. Figure now is the time to replace the nipples though.

Edited 1 April, 20215 yr by anewman

Where I live and how/when we use our cars, I usually factor in replacing all the bleed nipples at the 7 or 9 year fluid change, no doubt when you think about it, the hex "size" drops as the years and corrosion do their thing.

 

Luckily, when I changed the fluid on my daughter's 2009 Ibiza for the last time back in 2018, I did replace the front bleed valves, luckily I had a couple of new ones.

 

Changing the fluid every 2 years after the first change at year 3 does minimise the risk of this happening - a bit!

Just to agree with everything @KeithCheethamput - if a 6 sided socket isn't working, I do all the above, then carefully apply the molegrips. 

Anybody looking for bleed nipples for an FS III caliper these are a great price if you have Amazon Prime. There's some rubbish being sold on eBay with the same part number that's best avoided.

https://smile.amazon.co.uk/dp/B003VXPG20/ref=cm_sw_r_cp_apa_glt_fabc_WQFP15DHXQ49NJ8MFXFE

Edited 13 April, 20215 yr by anewman

I've just remembered that the last front calliper bleed valve that I had trouble with, I used a smallish Draper clamp on bench vise, that worked quite well, I managed to get a really good grip on the bleed valve and freeing that valve up by rocking/rotating the vise CW<>CCW it freed up without snapping off. That method might sound a bit crazy, but it did work for me.