As for the MC. I thought mine had gone bad due to a lot of pumping to get air out of the system. During the pumping my son was going all the way to the floor. Well I thought the o'rings on the piston of the MC might be damaged from traveling over territory that might be in bad shape from corrosion or pitting, because the pedal was floating full travel when I barely applied any pressure. So I disconnected the two lines traveling out of the MC and plugged them with machine screws of similar size. Now if the pedal moved I'd know for sure the piston orings were shot. But when I tried pumping the pedal it was hard as a rock. Master C is still in great shape to include not blowing fluid back past the sill upstream between it and the power pump.
After about 2-3 times around the car (FL, FR, LR, RR, and only bleeding the upper front screws and the one on each rear caliper, I discovered all calipers were bleeding completely clear with the exception of the front left which I'll replace with a new one tomorrow. I only got 191K and some change out of it but maybe I'll get more out of this new one.
So if you had already bleed and then snapped it off at least it's clean for now. If not you can do a couple of alternate methods. One is to remove the other lower screw and simply bleed it until all is clean (the paths are all joined I believe). As long as the top bleed screw is operational you can get all the air out (use a rubber mallet to help get the little bubbles moving along). If it is a rear caliper with only one bleeder screw remove the caliper from the wheel. Remove the incoming fluid line. While on your bench use a little oil bottle (the kind you use for precise oiling of say model train components that has a long fine nozzle and squeeze clean fluid into the caliper until it runs clear. Fill the caliper to the top, pump the line until it's running brake fluid then reattach the line to the caliper.
On the calipers with working bleeder valves (at least one), if you want to get the air out without losing a lot of good brake fluid, break the upper most nipple/screw free and return it to finger tight so it's not dripping, but now doesn't require a wrench to open it. Now open it one half turn and attach a piece of clear, highly flexable (TYGON) tubing over the nipple and into a bucket of old brake fluid. Run the tubing from the nipple up over the coil shock and down into the bucket. Make sure the tubing doesn't change the nipple position (either more open or closed). That way even if your doing the pumping yourself you'll have time to get out and see the bubbles developing in the high spot of the tube (any pnuematic shop sells tube that will slip snuggly over the nipple so no air can enter and make you think it's coming out of the caliper. Due to the pressure you build you will only lose a minimal amount of brake fluid while getting all the air out. Prior to this I had bought a so called system from my local auto parts store and the tubing was awful. The local pneumatic shop fixed me up.
I switched to synthetic brake fluid that exceeds DOT 3 and 4 specificaitons and doesn't boil till close to 500F. It's so clear now that it looks like it's not even there in the tube. My resivor was full of sediment too.
Good luck, hope this helps out. The school of hard knocks is an excellent, if not a time efficient, institution of higher and lower learning.

IF you didnt disturb the flex lines and calipers, you should be able to engineer a loose fitting at the inlet of the rubber line, and bleed there.
leave a small leak, and pump the pedal, or loosen and tighten the fitting as somone pumps the pedal.

IF there is air in the caliper, you are not doomed. You will want an assistant, but here is a way to do it.

clean the caliper and hoses.

loosen the line fittings at the caliper, and snug them up, so you know they are ready to move.

detatch the caliper from the mounting plate, and (gently) clamp the caliper on something just thinner than the rotor, hard wood, aluminum, or a stack of old pads.

Now, holding the caliper with inlet fittigs up, losoen the line(s) until a small leak is created,and squeeze the caliper fully back into the bore and clamp or shim it in this position. Now, the air has been forced back into the line, and the caliper is prevented from moving, so pressure on the brake pedal will force air out the loosened fitting. Try not to bottom out the master cylinder...put a block under the pedal.

repeat a necessary, tighten lines, and reinstall the caliper.


Be careful, take your time, and do check for leaks.

There's an easy way to find out. Pump the brakes until they feel solid. Keep the pressure on, and if the pedal slips right down again, you probably did indeed get a bad MC or somehow ruin it. But it's more than likely that pumping the brakes will compress the air and give you a good solid feel, indicating it's just the extra air the you didn't bleed out.

Spongy brakes or a lot of pedal travel indicates a classic case of air trapped in the lines. It is not uncommon for a 240 to be bled several times before all the air can be expelled from the lines (after a major operation such as replacing the master cylinder). I had to do some major caliper work and it took 2 seperate bleeding sessions (flushes) to expel all the air (about 1 quart of DOT 4 was used in each session). Driving the car in between sessions helps loosen up the air and make it easier to get the last little bit out.

God bless,
Fitz Fitzgerald.
--
'87 Blue 245, NA 231K

sounds like air still in there maybe you can get it all out with the other lower bleeder? it helped when i tapped on the caliper with a rubber hammer.