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D2 - Axles, Brakes, Suspension and Steering Brakes, Springs, shocks, steering racks, steering columns, suspension arms, wheel hubs etc.

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  #1  
Old 25th April 2020, 08:26 AM
spannerrash spannerrash is offline
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Default Brembo nipples seized.

Hi all
Whilst doing some work in my front suspension area I will be replacing the flex brake lines and also the "S" shaped hard lines that connect to the calipers. Consequently I will be introducing air into the system. Those of you who work on your own cars will know what's coming next. "the bleed nipples are seized" into the caliper.

Is there a solution? I will try pb blast and heat etc but my gut tells me the threads are going to come out with the nipples. Is there any insert kit / solution that someone has used before?

Thanks Frank
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Old 25th April 2020, 09:25 AM
MikkiJayne MikkiJayne is offline
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Oh dear. There's no easy solution for these unfortunately. Usually the link pipe unions are seized as well. I send them to BCS to get the screws and unions drilled out on a CNC. BCS can't currently make the replacement link pipes, but they are easy enough to diy if you have a flare tool. I cut the dead link pipes off before sending them away to retain the rubber sleeve on them which I refit to the new pipe before flaring.

Their workshop is shut down at the moment, but they are offering 20% discount to anyone willing to pay in advance for work when we're allowed out again.

I would suggest that you leave that area well alone for now until you know for sure when you can get the calipers back, otherwise the car might be down for many weeks.

Side note: I have read of a technique using ammonium aluminium sulphate to dissolve steel from aluminium but I haven't tried it yet. I will be attacking some pinch bolts with it as soon as I can get hold of some and will report back on what it does. If it works I'll try it on a scrap caliper too.
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Old 25th April 2020, 11:48 AM
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moltuae moltuae is offline
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Might be worth considering sending the calipers off to Pro-Calipers/Addiction Motorsports to be refurbished. I think the business is a one-man-band so he might still be open, and his work is excellent.
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Old 25th April 2020, 11:53 AM
spannerrash spannerrash is offline
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Thanks for the reply MJ.

I actually have a pair of brand new calipers I bought from main dealer a couple of years ago just in case they became NLA. It seems like an expensive option at £900 ish just because of seized nipples though.

I've already just fit new calipers on the rear so it looks like I'll be doing the same on the front.

I'll then probably send the originals away for a refurb.
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Old 25th April 2020, 11:54 AM
spannerrash spannerrash is offline
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Thanks for the info Mark
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Old 25th April 2020, 01:04 PM
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homer simpson homer simpson is offline
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Quote:
Originally Posted by spannerrash View Post
Thanks for the reply MJ.

I actually have a pair of brand new calipers I bought from main dealer a couple of years ago just in case they became NLA. It seems like an expensive option at £900 ish just because of seized nipples though.

I've already just fit new calipers on the rear so it looks like I'll be doing the same on the front.

I'll then probably send the originals away for a refurb.
Now seems like a good time to use the new calipers, no point holding on to them. As you have said, get the others refurbished when you have the time, they will look brand new.
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Old 25th April 2020, 08:33 PM
spannerrash spannerrash is offline
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Just found this image of a caliper that's on ebay at the moment. Is this an acceptable repair for the bleed nipple? Looks simple enough.
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Old 25th April 2020, 08:38 PM
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homer simpson homer simpson is offline
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Yes I would think so. One of my nipples was 'bunged' in the past by some cowboy who didn't want to get it repaired properly, probably stripped the thread. It went to BCS and they put a new larger threaded nipple in. I'll upload a pic if I remember tomorrow
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Old 25th April 2020, 09:07 PM
spannerrash spannerrash is offline
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This looks promising.

https://www.ebay.co.uk/itm/174156526149
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  #10  
Old 25th April 2020, 09:51 PM
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The_Laird The_Laird is offline
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I am so worried about contradicting Michaela, but, seriously. Do not use BCS in Nottingham! I have had front and rear calipers rebuilt by these cowboys, all have which have failed big time! They’ve leaked, had crossed threaded bleed nipples, had the two halves of the front calipers put back together wrongly, and much more. They are a seriously crap! DO NOT USE THEM!

Quote:
Originally Posted by MikkiJayne View Post
Oh dear. There's no easy solution for these unfortunately. Usually the link pipe unions are seized as well. I send them to BCS to get the screws and unions drilled out on a CNC. BCS can't currently make the replacement link pipes, but they are easy enough to diy if you have a flare tool. I cut the dead link pipes off before sending them away to retain the rubber sleeve on them which I refit to the new pipe before flaring.

Their workshop is shut down at the moment, but they are offering 20% discount to anyone willing to pay in advance for work when we're allowed out again.

I would suggest that you leave that area well alone for now until you know for sure when you can get the calipers back, otherwise the car might be down for many weeks.

Side note: I have read of a technique using ammonium aluminium sulphate to dissolve steel from aluminium but I haven't tried it yet. I will be attacking some pinch bolts with it as soon as I can get hold of some and will report back on what it does. If it works I'll try it on a scrap caliper too.
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