Master cylinder leaking

[astat1]

I had my Bendix power booster restored and bought a correct MC with engine side brake lines. Painted everything semi-gloss black and after about 500 miles the fluid has leaked out from the cap taking a lot of the MC paint with it. The cap and gasket were new and appeared tight and this seemed to have happened inthe last couple of days of driving. Can the heat cause an issue with the brake fluid?  The exhaust manifold is close to the rear line but I don't think I'm over the boiling point of DOT 3. I don't mind taking the MC off, stripping, repainting and bleeding again but is there anything that can be checked/done to prevent it from recurring? Thanks

1970 Coronet R/T Convert

[472 R/T SE]

I had the same thing happen.  New MC cap & rubber seal took care of it.

[Just 6T9 CHGR]

Also bending the retaining bale smaller (make the arch smaller) will tighten the cap more so it wont leak.....

Or you can get one of these with a nice machined flat sealing surface....

http://www.dodgecharger.com/forum/index.php/topic,30312.0.html

[astat1]

That's what I have. I bought mine from NAPA after reading that post. I'm using the cover and seal that was included. I have removed my MC, stripped it, repainted, bench bled it, and bled my brakes. I bought some aftermarket rubber seal that seemed to fit better. Not leaking with turning it side to side out of the car.  I took the car out for an hour and it is still leaking!! It is coming out of the front and rear of the cover. Tomorrow I'm going to pick up another cap and seal. The cap feels very tight but I will try to adjust it. Maybe I'm making too sharp of turns?

[Just 6T9 CHGR]

Hmmm interesting.  I have one as well as my friend locally with no troubles so far....the only difference possibly is the fact that I am using my original bale (as well as my friend who is also using an original cap)....its the same overall shape but its shorter in length.  That shouldnt have an affect on its locking though.
Hopefully you didnt get a bad casting

[astat1]

Thanks for the input. What I don't understand is why after 2-3 months of driving all of a sudden it would leak, so I don't think its a casting issue. New cap should be in shortly and I will give that a shot.