xivlia wrote:well the brake piston is stuck in solid. i used a molegrip no help.. mole grip with waterhose pliers, no help.. molegirp with rubber mallet no help. that thing will not move. and i dont see how a piston removal tool is gonna make any difference at all , i just dont see it having enough grip. itl most likely slide off. high pressure compressed air might work.

Oh FFS - Earsan. You asked for advice and you were given good sugestions and have ignored it once again! Just because "You don't see it having enough grip" these piston remval tools are specificaly designed
to do EXCATLY what they say on the tin and would have had that piston out in seconds.

Now you have undoubtably already mullered the piston with your mole grips and hammering, and by the sound of it you are about to trash the rest of your caliper in some vain atttempt to melt the old seal and release the piston. Has anyone on here or any of the You tube videos you have been surfing ever suggested that heating up the calipper and melting the seals is a good idea.........ermmm NO!

pip wrote:

xivlia wrote: high pressure compressed air might work.

How are you going o get high pressure compressed air to work if one piston is out, even if reinserted, but remember, high pressure brake fluid didn't do it!

Pip

100% right Pip and more sound advice Ersan. Air is compressable which in effect gives it a spring effect wheras fluid is incompressable providing an instant transmission of the force. The difference in the surface areas being acted upon by the fluid (I won't bore you with the full science) is what makes Hydraulics work and enable them to produce masive forces way in excess of any air system (think a JCB, car jack or even A HYDRAULIC BREAKING SYSTEM). I have only been working with hydraulics for about 25 years now so I know what I am talking about.

Now either take your caliper to someone with specialist tools and experience - or you might as well start trying to find another one now, as you will (i garuntee) fuck what you have left beyond use, and remember unless you pay top dollar for a fully refurbished caliper (if you can find one) - you are just going to be back at square one when you get your new 'second hand' caliper....ie needing to strip and clean it up again.

I only suggested the heat method as it was the only way i managed to get a stuck piston out of my rear caliper,

i did shock it loose with a dot punch inside the piston, and also wedged a socket in and then rotated it out,

Ersan you can shift it with hydraulic pressure you wont with air its not got the same pressure or powaaaaahs

Ricky - Dohhh! I missed that the heat was your suggestion I was so frustrated that Ersan had set about his piston with molegrips - despit being told that was a garunteed way to F**k em up, I guess I was just skim reading at that point.

Another good suggestion for the mix of tries was, again dot punch and then used the dent made and levered it against a spanner bare in mine the spanner and lever point were above the piston so that the pressure was on the spanner and not the piston preventing it from coming out,

If i were you i would rebleed the caliper, after triing to shock it loose or wedge a socket in about a 16mm off the top of my head and try rotate it to break the seal.

Rebulid and bleed and then stick something in the way of the free piston so it doesnt come out and pump like Arnold Schwarzenegger

This is better than watching TV!

My prediction....this caliper is fuked and Ersan will have to find a replacement.

why would heating the seals destroy the caliper? and why would hammering it with a rubber mallet destroy the caliper? i only hammered it to shock it, but il try ricks method this time. the caliper is like steel.... i think it should be able to withstand a few degrees of heat.

I thought the caliper was like aluminum.....

vfrman wrote:I thought the caliper was like aluminum.....

Pretty shit alu too, as it gets attacked VERY easy by all the road rubish, ideally need a quality powder coat or anodise, painting a caliper really doenst work,

Mines shafted allready so will be rebuilding again soon

porndoguk wrote:

vfrman wrote:I thought the caliper was like aluminum.....

Pretty shit alu too, as it gets attacked VERY easy by all the road rubish, ideally need a quality powder coat or anodise, painting a caliper really doenst work,

Mines shafted allready so will be rebuilding again soon

Oh dear, I guess my painting is also a temporary fix too then.....

Dude, if you put the caliper back together but leave the pads out and put a bit a wood or something hard in the gap were the pads and disc go you should be able to pump the piston out with the brake peddle, you'll get way more pressure with that than you will with a compressor and also it wont fire it out like it will with air (tho thats quite good fun). Or If you like making pipes up, jet washers are good fun aswell, you never know how far things are gonna fly!.

Cheers
Ian