Magura 7S fail (Calipers) on Amflow PL Carbon Pro after only 5 months!

[Bmin]

No coffee! I took the pics for recording after I took out the bleeding screw and saw the oil like colour, as I remembered this topic and statement, that Magura fluid was not blue.

Could be aged or been over heated, from what I learned. Maybe others had seen this as well when bleeding their brakes.

Overall I am happy with the MT7 and run Magura green pads.

 

[RickBullotta]

Fyi. I did bleed my Magura MT7 today for the first time and found by surprise brown liquid when removing the bleeding screw from the rear calipers. Can not tell if the shop did bleed the system with different liquid when doing first (mandatory) service at 300km - for that I had no complaint for the brakes and they did not mention to have done anything special. Front break was fine = blue.

Starting to bleed rear brake:

View attachment 188303

Opening screw rear calipers:

View attachment 188304

Brown fluid coming from the system:

View attachment 188305

Yikes. I hope the goons at the shop didn't use DOT brake fluid...

 

[Stihldog]

Coffee!? Even the new SRAM mineral oil by Epic bleed is green I think! Never seen oil that colour from Magura caliper internals. Shimano caliper sometimes black from seals or grey from shaving material from banjo thread (fluted banjo screws)

Yes, the SRAM mineral oil is green. Shimano is red. Magura is blue.

Baby oil is good for your feet

 

[Stihldog]

No coffee! I took the pics for recording after I took out the bleeding screw and saw the oil like colour, as I remembered this topic and statement, that Magura fluid was not blue.

Could be aged or been over heated, from what I learned. Maybe others had seen this as well when bleeding their brakes.

Overall I am happy with the MT7 and run Magura green pads.

Yes, the mineral oil darkens over time and use. It might be time for a full bleed and “flush”. Helps get any foreign particles or moisture out of the system.

I like MT7s also. I’m recently trying some organic pads(experimenting) but checking them more often.

 

[RickBullotta]

Yes, the mineral oil darkens over time and use. It might be time for a full bleed and “flush”. Helps get any foreign particles or moisture out of the system.

I like MT7s also. I’m recently trying some organic pads(experimenting) but checking them more often.

It really does look like DOT fluid though, doesn't it? That's straw yellow.

 

[Stihldog]

It really does look like DOT fluid though, doesn't it? That's straw yellow.

It does …hopefully it’s just well used and slightly discoloured.

 

[Bmin]

Gentlemen, if that is your straws yellow you should consult your doctor! The DOT I know from automotive is more a clear stuff.

I did a full exchange on front and rear brake with Royal Blood and in line with Magura recommendation in their video. Including careful mobility check of the pistons.

 

[ArmyOfEvilRobots]

AMFLOW may have claimed that they used the right kind of fluid, but the failure is consistent with using DOT in a mineral system, the color is consistent with DOT, and if they used "mineral oil" that isn't manufacturer spec, then they still screwed up, because not all mineral oils are the same.

Personally, I suspect that they grabbed the wrong fluid when they did the cut/route/bleed process.

 

[RickBullotta]

AMFLOW may have claimed that they used the right kind of fluid, but the failure is consistent with using DOT in a mineral system, the color is consistent with DOT, and if they used "mineral oil" that isn't manufacturer spec, then they still screwed up, because not all mineral oils are the same.

Personally, I suspect that they grabbed the wrong fluid when they did the cut/route/bleed process.

A shop bled the brakes after the OEM install. Usually no need to bleed a new Magura install at the factory - just cut to length, new barb/olive, and go.

I still think the shop put the wrong brake fluid in.

 

[RickBullotta]

Gentlemen, if that is your straws yellow you should consult your doctor! The DOT I know from automotive is more a clear stuff.

I did a full exchange on front and rear brake with Royal Blood and in line with Magura recommendation in their video. Including careful mobility check of the pistons.

Respectfully disagree. It's a VERY similar color to DOT 4 or 5.1 brake fluid.

 

[Bmin]

Respectfully disagree. It's a VERY similar color to DOT 4 or 5.1 brake fluid.

View attachment 188350

Ups! You are right. I have not been using DOT5.x before. Have an (over aged) batch of DOT4 from my moto here on the shelf that is very very slightly yellow.
However, the DOT is feeling differently on the fingers than oil. What came out of my Magura was definitely oil but may have turned brown due to age & heat?

 

[Valaminium]

Ups! You are right. I have not been using DOT5.x before. Have an (over aged) batch of DOT4 from my moto here on the shelf that is very very slightly yellow.
However, the DOT is feeling differently on the fingers than oil. What came out of my Magura was definitely oil but may have turned brown due to age & heat?

View attachment 188371

DOT fluids remove paint… and likely dissolve carbotecture plastic, automotive requirements are special butyl seals to contain and operate within a pressurised circuit master-slave/caliper

Maybe someone thought it would handle higher temps totally overlooking compatibility… people do it all the time with engine oils.