My brake pipe screw has stuck to the brake pipe
Discussion
Good evening.
I have a 2019 BMW M2 Competition. In 2021 I took off the standard brake pipes and fitted braided steel brake pipes. I am now putting it back to standard and I have purchased new BMW pipes.
The aftermarket pipes had swivel nuts which made fitting them very easy. The BMW pipes have fixed threaded connectors on both ends which means you would normally fit them by screwing them into the caliper first and then screwing the threaded nipple attached to the brake pipe into the other fixed end of the brake pipe.
My problem is that one of the front brake nipples has corroded to the brake pipe and I am fearful of putting any twisting effort onto it and breaking the pipe.
My first picture shows the offending threaded nipple which is corroded to its pipe.
My second picture shows the new BMW brake pipe into which it screws.
The bottom pipe has to poke up through the plate that is just right and upwards of the joint in the pictures and then the fixed black pipe with the nipple on it has to screw into the bottom pipe.
You can see slight damage already on the plastic wrapping the brake pipe where I tried to hold it with pliers.
The other side front came free with some penetrating fluid but this side has proved more obstinate.
Any thoughts on how I can free the fitting to enable it to spin on the pipe?
I have a 2019 BMW M2 Competition. In 2021 I took off the standard brake pipes and fitted braided steel brake pipes. I am now putting it back to standard and I have purchased new BMW pipes.
The aftermarket pipes had swivel nuts which made fitting them very easy. The BMW pipes have fixed threaded connectors on both ends which means you would normally fit them by screwing them into the caliper first and then screwing the threaded nipple attached to the brake pipe into the other fixed end of the brake pipe.
My problem is that one of the front brake nipples has corroded to the brake pipe and I am fearful of putting any twisting effort onto it and breaking the pipe.
My first picture shows the offending threaded nipple which is corroded to its pipe.
My second picture shows the new BMW brake pipe into which it screws.
The bottom pipe has to poke up through the plate that is just right and upwards of the joint in the pictures and then the fixed black pipe with the nipple on it has to screw into the bottom pipe.
You can see slight damage already on the plastic wrapping the brake pipe where I tried to hold it with pliers.
The other side front came free with some penetrating fluid but this side has proved more obstinate.
Any thoughts on how I can free the fitting to enable it to spin on the pipe?
Not sure if the coating goes in behind the nut itself ?
You could try a blow torch, to melt and free it up if so in case it is just that which is making it tight.
But more likely you may need to cut and remake the end off, although that will in turn leave it a little shorter.
Either way, I'd be patient with it, ideally you'd try and avoid re-doing the end.
You could try a blow torch, to melt and free it up if so in case it is just that which is making it tight.
But more likely you may need to cut and remake the end off, although that will in turn leave it a little shorter.
Either way, I'd be patient with it, ideally you'd try and avoid re-doing the end.
Fit the flexible line to the chassis side/stuck fastener, remove the caliper from the car, rotate the caliper to thread the flexi into the caliper, nip up, refit caliper.
Common option on anything old and grotty... but a little surprised a three year old BMW is suffering from this already!
Common option on anything old and grotty... but a little surprised a three year old BMW is suffering from this already!
poppopbangbang said:
Fit the flexible line to the chassis side/stuck fastener, remove the caliper from the car, rotate the caliper to thread the flexi into the caliper, nip up, refit caliper.
Common option on anything old and grotty... but a little surprised a three year old BMW is suffering from this already!
Why bwm steel is not different that other brandsCommon option on anything old and grotty... but a little surprised a three year old BMW is suffering from this already!
Especially on something cheep like. A brake pipe
Chris32345 said:
Why bwm steel is not different that other brands
Especially on something cheep like. A brake pipe
Because there is an internal BMW spec for anti corrosion coating on external machined steel components which suppliers need to adhere to that should prevent this happening until well after the warranty period has expired.Especially on something cheep like. A brake pipe
There's actually a massive amount of difference between manufacturers specs for things like this, it's why Mazda suffer from this sort of thing massively but Porsche doesn't.
E-bmw said:
2019 to now is not 3 years. 
Oh yeah, I read 2021 
But unless that's been out in the salt every winter and clocked up a load of miles I remain surprised to see this sort of failure. We used to copy the BMW AC spec for a load of machined steel bits because it was really well defined and laid out and this sort of failure mode was uncommon on their products.
poppopbangbang said:
Because there is an internal BMW spec for anti corrosion coating on external machined steel components which suppliers need to adhere to that should prevent this happening until well after the warranty period has expired.
There's actually a massive amount of difference between manufacturers specs for things like this, it's why Mazda suffer from this sort of thing massively but Porsche doesn't.
It really doesn't they suffer from as much rust as any other brandThere's actually a massive amount of difference between manufacturers specs for things like this, it's why Mazda suffer from this sort of thing massively but Porsche doesn't.
Chris32345 said:
poppopbangbang said:
Because there is an internal BMW spec for anti corrosion coating on external machined steel components which suppliers need to adhere to that should prevent this happening until well after the warranty period has expired.
There's actually a massive amount of difference between manufacturers specs for things like this, it's why Mazda suffer from this sort of thing massively but Porsche doesn't.
It really doesn't they suffer from as much rust as any other brandThere's actually a massive amount of difference between manufacturers specs for things like this, it's why Mazda suffer from this sort of thing massively but Porsche doesn't.
I have always done all my own spannering & have never had a bolt shear, a nut round, a nut/bolt seize etc on any of the several I have owned.
Not true of any other brand I have worked on except Volvo.
Master Of Puppets said:
Put some ATF fluid in a jar and prop it up so the union is sitting in it, leave it like that for a day or two and it's unlikely you
will have to revert to potentially weakening the pipe or damaging any of the surrounding area with heat.
If you are not in a hurry this is what I would do. Blow torch to follow as a last resort, the heat will destroy the coating on the pipe so don't do it unless you have to. will have to revert to potentially weakening the pipe or damaging any of the surrounding area with heat.
dontlookdown said:
If you are not in a hurry this is what I would do. Blow torch to follow as a last resort, the heat will destroy the coating on the pipe so don't do it unless you have to.
Agreedz spm in ATF or keep dosing with Plusgas or Bulldog BDX two or three times a day.As an alternative to a blowtorch, I often use a heat gun (20 quid jobbie from Screwstation) which can get fittings hot enough to help but not as violent as a blowtorch.
Either way the coating will be damaged by heat but a dab of grease down the pipe won't hurt and will help protect for a bit longer.
I cant offer any advice I'm afraid, however when I ended up needing to replace the brake pipes on the rear of my e90 when it was 10 years old, I ended up needing to replace the hard line too, as the steel line had corroded and expanded resulting in the same issue.
Its madness that a car as young as this would suffer the same, I'm assuming the coating may have been compromised when the lines were changed in 2021.
Its madness that a car as young as this would suffer the same, I'm assuming the coating may have been compromised when the lines were changed in 2021.
Many thanks to everyone for the advice. We left the three offending screws (one came undone easily) coated with Blaster and today applied heat for a short while using a cooks blowtorch. The three corroded screws freed up very easily. No damage to the plastic coating that remains visible. Job sorted.
E-bmw said:
Not my experience with them as a manufacturer.
I have always done all my own spannering & have never had a bolt shear, a nut round, a nut/bolt seize etc on any of the several I have owned.
Not true of any other brand I have worked on except Volvo.
I have always done all my own spannering & have never had a bolt shear, a nut round, a nut/bolt seize etc on any of the several I have owned.
Not true of any other brand I have worked on except Volvo.
A few years ago I did a full suspension refresh on an e39, I was dreading it as most of it had been there since the car was new (it was twenty years old and had covered 150k!), guess what? Not a single problem anywhere, with the correct tool even the rose bushes in the rear lower arms were a piece of piss, I was amazed..
...The sills around the jacking points on the other hand...
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