540i Brake Master Cylinder Seals

[RSK540iA]

Can one obtain a brake master cylinder seal kit for the E34 540i? My local brake specialist suggested I purchase a complete master cylinder from the agents (probably at great cost).

My brakes don't feel 'crisp', there appears to be some 'give' when braking accompanied by added pedal travel. It feels like pressure is bypassing the MC seals.

Any advice welcome.

Many thanks.

[Evan]

you can visually inspect the seals on the master cylinder... is there is brake fluid leakage you'll see it.. and if it dripped onto any painted metal --- well the metal will no longer be painted...

if they're leaking buy them at the dealer and replace them yourself... its an easy DIY job... careful with the brake fluid though... watch your paint

[stargazer_61]

BMW changed the design of the seal slightly. Where the originals had a hexagon shaped top, the new ones will be round. About $7 USD each and you need 2.

1) Grab hold of the line at the seal and pull up.
2) Get some needlenose pliers and pull out the rotting rubber from the master cylinder and from the line nipple
3) Press the new seal into the M/C, then press the line in. Make sure there are no gaps between the plastic line & the seal.

This is maybe a 5 minute DIY job if you are being cautious. Brake feel is improved and you aren't getting the "Brake Fluid" warnings from the OBC.

To reiterate what Evan said, watch your paint! Drape a towel or some plastic over your fender.

[markus]

easy job. noth seals will run u $5 if u order them. our dealer doesnt stock **** for these cars. or anything that isnt made within the last 5 years.

[Blitzkrieg Bob]

I don't think kits are avalible anymore. I haven't seen any in years, and most mechanics won't do rebuilds out of liability.

It's all new or remanufactured assemblies now.

[Tiger]

Yep, you can buy just the seal. Master cylinder as a whole is not that expensive anyway... online that is.

If you see seals leaking, you need new seals.

As for not being crisp, bleed/flush the brake lines until new fluids comes out for a while... and the new brake fluid will bring that crisp back.