gas station air to push out brake pistons?

[juntjoo]

I'm hoping it's possible. I have never removed brake pistons not really used compressed air much and I don't really have a need at the moment for an air compressor. so what other alternatives do I have if any? I'm about to rebuild one of my rear calipers. thanks

 

[TSIturbo91]

Why not just hook it back up bleed it and pump the brakes? Hydraulic force and compressed air are very different. Just one of the reasons you have to bleed the air out of the brake lines. But if you just trying to eject the piston it may work for you. I'm not quite sure if it will though. But good luck!

 

[juntjoo]

good suggestion. why could I not think of that? I guess I'll have to do it in a bucket or something to collect the mess. thanks

 

[jtmcinder]

Yes, "gas-station" air will work. Just don't forget to put a block of wood in there, because when it pops, it will move.

 

[juntjoo]

will I need any kind of adapter?

 

[jtmcinder]

I always used a trigger-nozzle on my own compressor. At a gas-station, use one of those plastic adapters that allows you to pump up a beach-ball.

 

[juntjoo]

Why not just hook it back up bleed it and pump the brakes? Hydraulic force and compressed air are very different. Just one of the reasons you have to bleed the air out of the brake lines. But if you just trying to eject the piston it may work for you. I'm not quite sure if it will though. But good luck!

can anyone confirm this will work? sounds like it should. also sounds like I should have the caliper in a bucket to collect break fluid once the piston goes right?

 

[pauleyman]

If you used compressed air keep in mind that piston will pop out hard. It will break your finger if it's in the way. This could also blow the boot up if it stays attached. You have a rebuild kit for the caliper? I assume this is why you're doing this otherwise there is no reason to remove the piston.

 

[juntjoo]

yes I do have a rebuild kit. but i'm inquiring about getting the break line attached to use hydraulic breaking pressure to remove the piston

 

[pauleyman]

Yes you could press out the piston with the fluid also. If you don't want to have to bleed the master also you'll need to keep adding fluid and plug the line up once the piston is out. This isn't a difficult job.

 

[TSIturbo91]

yes I do have a rebuild kit. but i'm inquiring about getting the break line attached to use hydraulic breaking pressure to remove the piston

Well if it's seized or hung up the hydraulic force would work good. Also most gas stations have the tire air chuck on there free air lines. Would you change the fitting on them to an air gun or something? You might not even need to bleed the line to get it to just pop out.

 

[juntjoo]

don't know how is use the gas station air. not familiar with how the caliper needs to be connected to an air source, so I just used the breaks. worked fine enough, with little spillage. guess I'll just have to bleed the system though

 

[Bud92gsx]

Again the backwoods easy, semi stupid,but effective way.Is to use the hydralics to push the piston out..Collect the mess is a gallon ice cream bucket.And add all new fluid when done.