front brake piston gen 4

hi i striped the front brake to clean the pistons after i cleaned them 1 piston will go back it will not move the other 3 are fine its sticking out about 5/8,ive tried using a g/ clamp it would move it,has any one got any idears what is wrong and how can i get it back in,ie do i need empty the fluid,and blow the piston out,also will draining the brake fluid on the front require the ABS to be bleed aswell,hopefully someone can help,cheers,also just a heads up on the gen 4 theres 2 circlips on the back of the front brake on the ends of the 2 pins,i didnt know they were there:worked_till_5am:

Are they 4 or 2 pad Calipers Paradoc, I'm just curious about that...

You sure the piston is in square ?

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Cant help the op. But yhey are 2 pad.

What comes out must go in.... Sounds like either it's not in square or pinched seal ? Did you have them right out?

bananaman said:

What comes out must go in.... Sounds like either it's not in square or pinched seal ? Did you have them right out?

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thanks guys no it didnt come out fully,if i take the fuid out of the front brakes to take the pressure offf will i need to just bleed the front,or would effect the ABS pump,i think thats a dealer job,its 4 pistons in each 1 pad each side

paradoc said:

thanks guys no it didnt come out fully,if i take the fuid out of the front brakes to take the pressure offf will i need to just bleed the front,or would effect the ABS pump,i think thats a dealer job,its 4 pistons in each 1 pad each side

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all sorted it was not in straight,i blocked off the other 3 pistons from moving, got a mate to gently to apply the brake a few times ,and wiggled the stuck one, and it went straight in,thanks for your help guys,happy days,

I laughed at my "in square" comment... in a round hole of course lol...

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