It's your brakes man! Brakes are the one area on a car that I don't get to have a beer until after
the job is done!
Of course, that was back when beer wasn't being rationed like TP.
So you had to take the brake line off the caliper? Anytime you open that system up, air is going to get in there. Air compresses nicely and does bad things to the ability of your brakes to work as intended. There is also water in air, which I wouldn't want in my lines but I don't think the water is as big a deal as the loss of braking power that happens when that compressible bubble of air gets in the line.
So, with air in the lines, you can't stop in as short a distance - not a big deal until it is, and then it is a very big deal indeed.
Bleed those brakes.
On this topic, does anyone here have experience with the "Motive Products, European Power Brake Bleeder" on Amazon? I've been thinking about flushing the lines on my fleet and this makes it look very easy to pour through gallons of brake fluid all by myself.