Hi,

My friends accord have a Brake Fluid Leak "not visible"!. we checked all the wheels, inside the engine compartment, nothing. If he pushes the pedal all the way it will leak out all the fluid and the pedal is spongy. If he shut off the car the pedal gets hard.

Any thoughts!

Thanks...

 

does it have rear drums? the wheel cylinders could be leaking and u wont see it or it could be the master cylinder

 

We checked the cylinders they are good. there are not visible leaks. could it be the mc leaking from inside?

 

so the pedal just goes to the floor and u are losing brake fluid?

 

exactly. If the car is on you push the pedal it will go to the floor and it will leak all the fluid. If the car is off you push the pedal it will harden but it will still leak all the fluid. We checked the front wheels brake lines and the rear drums.

 

Look down by the pedal at the pushrod. It could be leaking there.

 

Check that MC.
With the engine on you have power assist from the booster, with it off you loose the assist and the brakes are manual. Manually you cannot provide the same pressure to the MC piston, thus you cannot roll the internal seal of the MC. With the engine on, there is more pressure at the MC piston and you can blow the seal.

 

I'll check it out tomorrow and get back with the updates