Suspect brake hose

[Tintin]

Last year I replaced the brake fluid reservoir and the low pressure hoses between it and the master cylinder and renewed the fluid in the entire system. The hose was from one of the well known specialist suppliers and is marked "EPDM 27/17-22".

I now notice the clear amber fluid in the reservoir turning slightly black - darkest at the bottom. I seem to recall reading somewhere that this is due to a reaction between the fluid (Dot 4) and the rubber of the hose.

Can anyone confirm if this is true and tell me where to buy hose that will be unaffected by such a reaction?

Robbie

[mike020150]

Being a suspicious type, I'd say you always have to be wary of quoted specs when you buy components but buying from a well-known name should avoid most such risks. Short of performing your own chemical analysis of hoses, there's not a lot more you can do!
All brake fluid will darken with time due to the small wear particles of rubber etc which accumulate in it. These circulate slowly and are one of the reasons that brake fluid should be changed regularly. With modern cars, the particles risk blocking the fine holes in ABS units making it even more important that the fluid is changed. Mike.

[Tintin]

I agree, but wouldn't expect proper brake hose to react in this way after only 11 months. The hose is stamped EDPM and AFAIK EDPM is the correct material for brake hose, so either it is not what it says it is, or the master cylinder rubbers are on their way out!

Fuel or water hose of course should NOT be used for brake fluid because a reaction/osmosis will occur.

I will try another source.

Robbie