Brake master o-ring

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Aug 14, 2007
replaced the master w/rebuilt one but apparently the o-ring between resevoir and master is leaking slightly enough that i have to riple pump the brake to stop. the parts store o-rings are either a hair small or big but they dont even look right. can I get that o-ring from toyota? I've yet to have good brakes and am tired of almost running over atv's on the trail
Here's the parts diagram. I don't know if you're replacement is the same. It doesn't make sense that a bad gasket between the reservoir and the MC would cause you to have to pump the brakes. Sounds more like there is air someplace. Did you bleed the master cylinder? have you bled or re-bled the brake lines?
brake master cylinder.JPG
yeah i've seen the diagram on sor, it doesnt show the o-ring. when i press the pedal i can hear the leak at o-ring, air is a possibility just changed left wheel cylinder.
it seems im hearing the leak between res. and mc. cleaned with brake clean and dried. when i pushed the brake once you could hear the leak and slight fluid appears around base of res. more pumps on brake more fluid. will test booster tommorrow am when dealing with my sputtering fuel issue.
OK. Maybe you have a late-model FJ60 (post 4/85) master cylinder. Position 47202T has part number 90562-18151. The MSRP is about $4, though. I guess it's cheaper than an OEM master cylinder.
brake master cylinder 2.JPG
yeah it is cheaper than the $90 I spent on a master. it probably would've helped to tell you guys I have an 89 fj62. have a possible leaky booster AND a weird sputtering? Think maybe these two could be related?
well that also raises the question, can the booster be leaking from the lack of a paper gasket between the MC and booster? Also thanks for a response on the sputtering, I added somemore info on that today aswell. I can hear sucking(vac. sound)from that region but can't pinpoint it.sounds louder closer to enginge than booster. I've tried to finger every hose and vac. in that area trying to pinpoint the sound. But I always seem to wind up with my ear on the intake at 5and 6 where the sound is most prominant. I tried the booster test and think I'm not doing it right. I changed the MC weeks ago sputter started few days ago.
So you hear a vacuum-leak type sound from where the booster takes it's vacuum from? And...?
and I have taken a break for dinner will work throught the night...well some of it anyway theres a cold front in town and I cant take the low 70's. But that is my starting point when I get back to it.

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