It's called a "bleeder" valve 1st of all.The reason it's there is to bleed out the air and water that build up over time and even to bleed out old brake fluid from a car's system.It's always done if the brake system was ever opened,meaning changing a brake line,a caliber,a wheel cylinder in the case of older cars with drum brakes and if the master cylinder was ever changed.But NOT if just the master cylinder was opened to check for fluid level.If the bleeder valve is leaking,I suggest one of the following:
Since you said that the caliper is new, if it is defective you should return it for a replacement before the warranty expires. As this type of defect, if it really is defective, does not appear until the caliper is installed and the brake fluid is refilled, you should be able to get another caliper at no charge.Whatever you do, don't try to repair the caliper yourself if you can exchange it.
just replace the whole caliper.
Rebuild the cylinders on that caliper.
If the caliper is sticking or leaking it is possible to buy a rebuild kit and replace all parts that are worn inside. If the caliper has a cracked or broken housing then the unit can not be repaired and must be replaced.
Take some screws, screwdrivers, nuts and spanners firstly open the leaking area fix it with some well branded glue , fill it with cement and tile it. Screw it and fix nuts with spanner.Now it is fixed.
You replace them!
Either your emergency brake is hanging up or your wheel cylinder is leaking fluid and needs replaced if drum brakes and if disc brakes the caliper could be bad.
NO, and in fact what you are proposing is extremely dangerous !The only fix for this is a new part fitted by a competent professional.
how do i fix leaking spray pump on a 2 barrel carburetor
The fix is replacing the leaking part.
Replace
The only fix for a leaking heater core is to replace it.
It could be leaking from a number of places. Some could be a simple fix and others not so simple. Need more info as to where it is leaking.