brand new brake line bubble what gives

[Firstbmw528]

03/98 528i replaced all the rubber lines with new rubber lines the in between up front by the ABS module was replaced then bubbled so I was sent another line and here we are two weeks later and it has bubbled again same line. what gives? the only thing strange about my ABS is occasionally it randomly engages in reverse and at low speed.

I just used INPA today to read my wheel speed inputs and they all were perfect with no anomalies. The pads and rotors are new. The brakes are recently bedded as in two days ago.

I did activate the ABS pump via INPA on accident could that have bubbled the line?

[Dave Sal]

Are these aftermarket brake lines?

[Firstbmw528]

Rein brand brake likes just put on my third since October this evening.

[fullthrottle540]

Bubbled lines can only be from poor quality or deteriorated lines

[Firstbmw528]

Perfect Thank you for the answer I wanted to make sure there wasnt a way I was causing it or if other parts on my car were causing it.

[adm750]

Firstbmw...I'd have to agree with Fullthrottle540.... I'm thinking along the lines of a bad crimp on the fitting, letting fluid past the fitting nipple allowing it to go in between the core tube and the outer cover, or between the layers of hose and the reinforcement braiding.

The only thing I can think of that you could possibly do to cause this is that somehow twist is being introduced in that line during installation (since neither end has a swivel fitting...). This would probably be very difficult to do during install, but it's just a thought. ie...if you are allowing the fitting to rotate on the hose when tightening, this might affect the crimp and make it leak. Sometimes there is simply just air trapped in the assembly and it gets pushed out when the assembly sees it's working pressure....which can cause cover bubbles on thermoplastic hoses (like the Teflon braided lines) or blisters on a multi-layered rubber hose like these stock ones.

This is one area you don't want to take a chance...and I hope Rein asks for your brake lines to be returned so they can evaluate them. Sounds like a QC issue that could cause concern for more people than just yourself. If I were you, I might have to bite the bullet and go OEM here on this line. If this is a true QC issue with Rein, then who knows how broad it reaches...meaning, you may keep getting lines from a batch of production that fails to meet the quality standards.

good luck,
tony

[Firstbmw528]

Thanks for all the info Tony I plan to go OEM once I exhaust my supply of brand new rein lines. When the first one bubbled there was a miscommunication and advance sent me 3 so I’m hoping 3rd time is the charm.

I do know I am not twisting it so at least I know I haven’t done that.

I did notice when doing the brake line my rear rotors while spinning rather than having slight resistance or dragging spin and catch every so often when in gear. I have a video I’ll be posting when I can.

I have no hot brake smell or excess dust but I found it strange and wonder if it is a BMW thing or maybe the pads are catching the slots in the rotors?

[Firstbmw528]

So update another bubble in the new brake line seems like they bubble within a week. I think I have one more I received for free so I’ll slap that on and if it goes I’ll have to source one from bmw or fcpeuro.

[crazy4trains]

So update another bubble in the new brake line seems like they bubble within a week. I think I have one more I received for free so I’ll slap that on and if it goes I’ll have to source one from bmw or fcpeuro.

Did you ever verify that all you heat shielding is in place? Probably unlikely but heat could be causing this problem. The heat shields are there for a reason.

[Firstbmw528]

Heat shields have been gone since I’ve owned the car and the oe brake line was just fine I replace it as preventative maintenance.

[geargrinder]

03/98 528i replaced all the rubber lines with new rubber lines the in between up front by the ABS module was replaced then bubbled s

Odd. Where were these purchased? Could they be counterfeit lines not rated for pressure? Somebody could easily whack up some non-braid-reinforced lines like that and toss them on eBay and have them fit fine and 'work' for a little while, but be dangerous as hell.

[Firstbmw528]

Actually 2 or 3 from advance auto parts and 1 from auto zone all rein brand in original packaging that is why I am so confused.

[Firstbmw528]

Update put in my last rein brake line today and bled brakes in the process found out my front drivers and rear passenger rein brake lines that are 2 months old now have bubbles is it possible my vehicle is causing this or are these just super sub par parts

[Firstbmw528]

Would meyle brand be more reputable than rein?

BMW oem on fcpeuro are a bit outside of my budget at the moment.

[JaxPlanet]

If you are giving up on Rein, I think ATE would be a better choice than Meyle since they are an OE for BMW's brake systems. That said, I bought FCP's SS braided brake line kit, which were made by Techna-Fit. A set of 6-lines were $78 delivered. The only problem I had was the lower ABS line wouldn't seat properly. FCP stumbled on this problem so I called Techna-Fit directly and Chris sent me replacement in two-days at no charge, which resolved the problem.

FCP PN: 1220 for sedans and 1225 for tourings

[Firstbmw528]

Thanks for the info I was coming to add another update I just replace the in between hose with the last one my 3rd rein and it has already bubbled in 2 hours in two different places on the line all I’ve done is bleed the brakes it hasn’t even been off the jack stands.

And the other rein brake like by the abs just bubbled as well in two separate places on the line. While on jack stands just after bleeding. It is only 2 months old.

What could I possibly be doing bleeding or wrong with my braking system to bubble all of these brake lines I’m beginning to wonder if it is my issue

[Firstbmw528]

Most up to date left the car on stands pending figuring out an explanation why the bubbles happened decided to test the pedal and see how it felt and with one pedal press the bubble on the drivers side that appeared today burst. so now I have an unusable car and am extremely confused it seems there is an issue present with my bleeding method or my car because in today alone 3 brake lines that had been fine for 3 months suddenly bubbled one had two bubbles and one burst as well. what gives?

[BMW540san]

I got lost in these posts in respect to the reason but if hose quality turns out to be issue, I've used ATE (made in Germany) for 2 lines in engine bay next to headers and FTE (made in Czech Republic) for lines to calipers. Both have been installed on my 528 and 540 for 5-6 years now with no issues.

[Firstbmw528]

Thank you very much. So far the only reason suggested was part quality. I am attempting to use this thread to ensure that there are no possible faults with the vehicle to cause these issues. I am using DOT 4 Synthetic fluid as recommended for the car so I am at a loss. I will order ATE this time around or stainless but wanted to ask around to see if anyone thought the issue was related to my vehicle.

[BimmrMeUpSnotty]

If you are giving up on Rein, I think ATE would be a better choice than Meyle since they are an OE for BMW's brake systems. That said, I bought FCP's SS braided brake line kit, which were made by Techna-Fit. A set of 6-lines were $78 delivered. The only problem I had was the lower ABS line wouldn't seat properly. FCP stumbled on this problem so I called Techna-Fit directly and Chris sent me replacement in two-days at no charge, which resolved the problem.

FCP PN: 1220 for sedans and 1225 for tourings

+1 on ATE.
Jax, what was the problem on the TechnaFit kit? I have the same kit, not yet installed. Part #1225

[Firstbmw528]

I’m in between an ate and fte set from pelican or the stainless from fcpeuro wonder if they corrected the incorrect part issue. I just don’t wanna order new parts until I confirm it’s faulty parts not faulty components on the vehicle thought I’m unsure how to do that

- - - Updated - - -

Jaxplanet
How long ago did you have this issue with fcp I’m considering that set but don’t really have time for waits and replacements since this is my daily.

Thanks

[cnn]

- I use FTE or ATE hoses, they are OEM, about $12/each or so at rmeuropean dot com.
- Make sure you replace all 6 hoses.

There is a DIY I wrote about 6 years ago...

https://www.bimmerforums.com/forum/s...er-Seals-Boot)

- - - Updated - - -

- Also, braking system is a life-and-death matter, I only use quality OEM hoses, they are OEM and cheap anyway, I do not understand why people even play with Rein or Meyle parts, which are likely made in China anyway.

[geargrinder]

Would meyle brand be more reputable than rein?

I do not understand why people even play with Rein or Meyle parts, which are likely made in China anyway.

I was gonna post a defense of Rein but then realized I was reading "Reinz" (totally legit excellent supplier of gaskets/seals/sealants) ! I think that's happened to me before from speed reading.

OK yeah, eff Rein then!

What could I possibly be doing bleeding or wrong with my braking system to bubble all of these brake lines I’m beginning to wonder if it is my issue

What's your procedure? I can't imagine it is either unless you have some unusual method...

Since you now have a truly burst one to inspect - can you confirm that line has a braided steel core? Its not just a fiber reinforced hose, is it? I assume the outer rubber is bursting and not the actual braided bit? Like pressure is seeping past the metal braids?

Post pix if you can manage it would be interesting to see.

+1 on ATE.
Jax, what was the problem on the TechnaFit kit? I have the same kit, not yet installed. Part #1225

Also interested in what fit problems happened...

I bought the TechnaFit kit for both the E46 and the E39. On the E46 I did all the lines, all working great.

For the E39, so far only used the rear lines, since my front caliper lines were already replaced a few years back.

I'd been thinking reading this thread "oh yeah I should do those engine bay lines" which are still sitting on my 'new parts inventory' shelf... but you know. NorthEast winter and stuff. The 'when it gets warm' car to do list is geting LOOONGGG. My front rotors are ugly and calipers probably need cleaning up anyway, so probably it'll be a front brake job come spring.

[Firstbmw528]

Yea I didn’t realize they aftermarket replacement parts were that low quality I’ll sound like a broken record but before the bmw part supplier never seemed to matter.

They’re actually made in Turkey weirdly enough.

The bubbles are actually only the outer layer but I did dissect a bubbled line and you’re correct these rein lines are only rubber with braided fiber reinforcement. I couldn’t located the area the brake fluid was leaking into the outer layer though.

My bleeding procedure is the same I think any one with none of the proper tools uses. I put my wife in the drivers seat have her pump the pedal 3 times and hold then open bleeder until pressure release close and repeat. Start at the caliper farthest away from the master and bleed each until caliper closest.

The only thing that may be strange is I typically bleed each caliper 3-5 times before I move to the next caliper because I was also swapping fluid for new.

On that note someone I know suggested it may be my fluid. I am using generic DOT4 synthetic brake fluid a store brand of some sort.

[geargrinder]

Crap there's NO WAY that should cause a bubble! I thought you were going to say maybe you used a pressure bleeder with 90psi or used some ABS pump function. The ol' wife pump-and-bleed (shut up) there's NO WAY that should EVER be able to do anything like that.

Check the OEM lines if you haven't tossed them yet but I know the corner rubber lines are for sure steel reinforced inside. Anything that isn't seems negligent.