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Caliper pistions.............

574 views 3 replies 3 participants last post by  SHIVER ME TIMBERS 
#1 ·
Got a question about brakes….
How do you extract pistons out of the caliper ?
I usually do it by pumping on the lever as much as the pistons come out them selves …..Actually one of them extracts completely and after the fluid disposes the opposite one is already enough out of the caliper body to be pulled out with a suitable tool .

But what if a piston is stuck ?? You cant pull it all way out with any metal tool like a pliers….as the pistons are made out of a brittle material ….Have had a few bad memories on this item……

On some cases like hayes and other non banjo hose endings like Juicy 3’s and …..i always seal a pump hose on the bridge hole between the two halves of the caliper while they are apart …and with air pressure they pop out…
..But again what if you got stuck in a situation like have now… A Juicy 5 caliper on the half that the hose comes into……the bridge hole as open on both ends……and I wont risk pulling on the piston as it can break…….

Also another thing ……..The seals which seal the pistons….they are square rings…..i mean O-rings with a square profile ….but one of their faces are slightly wider than the other…….so slight that couldn’t be seen with out a super close up…..

Which side should face inward and which one out…….by experience on previous Juicy’s I remember the wider face places towards the inside of the caliper I mean towards the pad ..And the other face towards the caliper body Right ?
 
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#2 ·
Compressed air blower tool with a rubber tip you can press tightly onto the caliper nipple or line hole using an air compressor or air tank with suitable pressure. Have a thick towel or similar object over the whole mess before you blast the compressed air...for obvious reasons. You can also put enough brake fluid in a container just big enough to hold the caliper and let it soak for awhile. Have the bleed barb out for this process to let as much fluid as possible to enter the caliper body. I'm not much for using other fluids to clean brake parts. Some are suitable and some are not. Metal is somewhat porus and can retain some residue from some fluids that are not ideal for a clean brake system, and they can leech out of the metal and into the brake fluid later under operation. I know that sounds a bit anal, but hydraulic brake systems can be extremely sensitive.
 
#4 ·
TNC said:
Compressed air blower tool with a rubber tip you can press tightly onto the caliper nipple or line hole using an air compressor or air tank with suitable pressure. Have a thick towel or similar object over the whole mess before you blast the compressed air...for obvious reasons. You can also put enough brake fluid in a container just big enough to hold the caliper and let it soak for awhile. Have the bleed barb out for this process to let as much fluid as possible to enter the caliper body. I'm not much for using other fluids to clean brake parts. Some are suitable and some are not. Metal is somewhat porus and can retain some residue from some fluids that are not ideal for a clean brake system, and they can leech out of the metal and into the brake fluid later under operation. I know that sounds a bit anal, but hydraulic brake systems can be extremely sensitive.
plus 1.......I clean parts with clean brake fluid (or mineral oil depending on what brakes use) and a clean rag
 
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