Master cylinder leak

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71scamp78

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My master cylinder was leaking out of top of fill tank so I replaced with the newer style aluminum one with plastic tank and caps. The new one has fluid that pushes out of caps. Never had this issue before what do you think the problem is. Front has disc brakes and everything is new on front including lines , hoses and calipers. Back is drum
 
With shoes in contact with the drums, when you pump the brake, the wheel cyl move out only, you don't waste pedal moving the wheel cyl in/out, just to be pulled back by the springs .
 
inertia said:
With shoes in contact with the drums, when you pump the brake, the wheel cyl move out only, you don't waste pedal moving the wheel cyl in/out, just to be pulled back by the springs .
Click to expand...

Ok I'll give that a try but what is causing the fluid to push out of the master cylinder when braking. Just air in system or..
 
If there is residual air in the system, when you pump the pedal, it comrpesses the air, and when you release the pedal, it can push fluid back into the reservoir quite violently .
To test, with emergency set, with reservoir caps on, - have someone pump brake to hardest, remove cap, have pedal released, there should be next to no return to the reservoir, any large return, or " fountain " of fluid is likely air . With shoes against drums, springs can't cause return .
CAUTION. . Brake fluid is excellent paint remover,. Rinse with water immediately. ! ! !
EDIT
 
inertia said:
If there is residual air in the system, when you pump the pedal, it comrpesses the air, and when you release the pedal, it can push fluid back into the reservoir quite violently .
To test, with emergency set, with reservoir caps on, - have someone pump brake to hardest, remove cap, have pedal released, there should be next to no return to the reservoir, any large return, or " fountain " of fluid is likely air .
CAUTION. . Brake fluid is excellent paint remover,. Rinse with water immediately. ! ! !
EDIT
Click to expand...
Ok sounds good I'll give it a try tomorrow. Appreciate the help.
 
inertia said:
If there is residual air in the system, when you pump the pedal, it comrpesses the air, and when you release the pedal, it can push fluid back into the reservoir quite violently .
To test, with emergency set, with reservoir caps on, - have someone pump brake to hardest, remove cap, have pedal released, there should be next to no return to the reservoir, any large return, or " fountain " of fluid is likely air . With shoes against drums, springs can't cause return .
CAUTION. . Brake fluid is excellent paint remover,. Rinse with water immediately. ! ! !
EDIT
Click to expand...
Well bled brakes today had full pedal. Took for a drive and had to pump brakes because fluid coming out of caps on reservoir. I did apply emergency brake while bleeding them bled all four corners no air. Took caps off like u said no pressure built up or anything. I don't get it I had issue the the original style master cylinder. I've never come across an issue like this. I'm stumped
 
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