Why is my master cylinder throwin up brakefluid.

[afroman006]

I recently replaced my master cylinder with a rebuilt one from autozone and now I have a leak coming from somewhere. I tightened the line fittings as much as I dare to but there is still fluid dripping from somewhere. It is a significant leak, after about a week and a half the front reservoir was empty. Judging by where the fluid is on the outside of the MC, I am guessing it is coming out of the top somehow. But I cant figure out why. Anyone have any ideas?

 

[Gixx]

Check the gasket under the cap -

You can bend the retaining bar "spring" some to cause it to apply more pressure to the cap. My rebuilt unit did the same thing...

 

[divorced]

Plastic or steel resevior?

 

[afroman006]

Steel.

 

[divorced]

Not for sure, maybe the gasket at the top?

 

[dieselponyexpress]

Same with my rebuilt unit.

Leaks from top. I inspected the reservoir and detected that the surface isn't machined well. There are small cracks and sometimes the upper edge measures less than 1mm.
Obviously not a perfect seal.

I'm thinking of an additional homemade gasket now . . .


Regards,
Walter