Bad Brake master questions.

[LivingLegend06]

So it looks like my brake master is on the way out. Under braking my brake pedal slowly sinks to the floor, sometimes I have to pump it once to finish a high speed stop(freeway offramps mostly). Correct me if I'm wrong, but I'm assuming this means brake master cylinder)

Car is an 86 eta

My question is: what are my options from here?
I'm thinking about just picking up a used brake master off the boards here, is one from any model fair game? does abs/no abs matter? Would a rebuild kit be cheaper/better/easier and where are those available through?

Thanks,
-Alex

[jlevie]

That can be a bad master cylinder, or it can be a leak elsewhere in the brake system. Do a through search for leaks and if none are found, replace the master cylinder.

[vic_325]

i had this same problem for a while and thought i just needed to bleed the brakes... so i did but still had the same problem. then just this sunday i was driving i stopped at a 4 way intersection and after i came to a complete stop the pedal went to the floor lol lucky for me i had already stopped the car!

my car is a 86 eta 5 speed no ABS.. and i used the brake booster and master from my parts car (87 auto with ABS) there was a difference because the abs car master only uses two lines connected to the master..

the third one that the non ABS car uses has a threaded plug. i just unplugged it and compressed the piston to make sure fluid was getting pumped through.

the car stops now!

[LivingLegend06]

Good to hear vic, I'll be looking for any good used master cylinder I can find.

Thanks.

[jlevie]

Get a new (not rebuilt) master cylinder. Brakes are too important to trust to a used master cylinder.

[asubimmer]

Good to hear vic, I'll be looking for any good used master cylinder I can find.

Thanks.

I have a good used master out of my 318is. It was removed for the larger 27 master.

LMK

[LivingLegend06]

Thanks guys, I already picked up a used one locally for cheap.