Brake accumulator and pump

Good morning all, some advice please. I recently changed the brake accumulator because the pump was coming on every two or three pedal presses. I've noticed that now although the pump comes on only every five pedal presses, it stays on for longer than it used to. Why is this? :confused2:

plumbfisher said:

Good morning all, some advice please. I recently changed the brake accumulator because the pump was coming on every two or three pedal presses. I've noticed that now although the pump comes on only every five pedal presses, it stays on for longer than it used to. Why is this? :confused2:

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Because it now has a pressure filled bladder to pump against, as pressure builds the bladder is compressed so more fluid is required to be pumped. When the pump was pressurising against a deflated bladder when it compressed the rubber it was just pressurising against the steel sphere. So less fluid was being pumped to get up to pressure.

Right, I can understand that, thanks. After the pump has cut out the level of brake fluid is on the max line on the reservoir. Is that ok too?
(There's been talk elsewhere about the horrendous cost of a new brake pump, that's why I'm being so fussy about this!)

plumbfisher said:

Right, I can understand that, thanks. After the pump has cut out the level of brake fluid is on the max line on the reservoir. Is that ok too?
(There's been talk elsewhere about the horrendous cost of a new brake pump, that's why I'm being so fussy about this!)

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Yes that is how it should be. To top up you run pump and top fluid when it stops. Fluid will always be above max after car has been stood for any long length of time. That is why there is lots of excess capacity in the header tank.