Hissing from behind dashboard ?

[xpress]

just to update, there's no hissing it was from the filler cap where the wire go in, there's no hissing now when the wire is put in and it was only slight. might be a vent hole. no loss of fluid. now having trouble with getting a firm pedal, it keeps on going firm after 14 presses of the pedal, all pads and drums are biting i can hear them, all fluid is moving i can feel it with my hands on all hoses and pipes to calipers etc, and then a couple of seconds not touching the brakes and then i can push the pedal to the floor. pedal doesn't stay to the floor though and no loss of fluid. bled the system with another 500ml with eezibleed at 20psi. the o/s front caliper lower drain/bleed screw, was dry even with lots of pedal pushing, finally got a few drabs of brake fluid out of it today, not sure what's stopping it from flowing there, maybe trapped air, hence why they sometimes supply calipers primed with brake fluid? thinking of chopping in these calipers now for recon. how can you prime the calipers with fluid yourself? thanks.

[kevtherev]

My dear friend
you have some serious issues with your brakes
fluid should not be felt moving in the pipes
there is a lot of air in your system.
Calipers do not come primed nor do they need to be on this type.
The pistons in the Calipers moves half a milimetre and the pedal is hard
Again.. Fluid does not travel in the pipe it transfers energy.
When air is mixed in with fluid the air compresses and the pedal is soft

[xpress]

you're right, shouldn't feel any movement of brake fluid. sounds like air in the system too, shouldn't be so noisy. feels that way at the o/s front caliper that's not draining as well as i think it should in my opinion. thinking about chopping these calipers in now. will it take another litre and keep bleeding? going to try the stick on the brake pedal method with the filler cap off.

[kevtherev]

Have you followed the order each wheel should be bled?