I'll be replacing a master cylinder in an 84 244GL this afternoon. I haven't done any non-routine repairs on brakes in a long, long time. What I've forgotten is the best / correct way to bleed the brake system.

As far as I understand, each brake line is bled at the caliper. Give it a few pumps on the pedal to get the air out... but how do I know when to stop?

I'll be performing this repair in 1.75 hours. Any and all suggestions are welcome.

Thank you.

Well it's time. Thanks for all the help, everyone.

You shouldn't have to bleed the whole system on a MC change.

Check out B.C. Bob's earlier post here.

Bench bleed (on the car) using lines like these (from Rob Bariess). Buy a cheap 2' line (European ISO bubble flare) and cut in two.

When MC is bled, prop the brake pedal down about 1 1/2". This will keep fluid in the MC while you reconnect the car's lines to the MC.

Remove pedal prop and, with connections slightly loose, follow Bob's "reverse bleeding" procedure from the LF caliper, then tighten lines.
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

Make a 3-hose bleeder jug for bleeding the front calipers, you'll be happy you did. bleed order: left rear, right rear, right front, left front(longest-->shortest).

Buy extra fluid, two quarts of Castrol LMA DOT4 is what i wind up using for full fluid replacement. A lot of people here like the ATE blue fluid too.
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80 262C Coupe- (FSO black, M46, original) 82 244GLT- (auto)

Bench bleed the m/c. Install the lines, then bleed according to sequences in the 700/900 FAQ at the calipers. Fill reservoir, install hose on bleeder at caliper, open bleeder, push pedal (since the m/c is new, you won't have to worry about pedal stroke and seal wear), close bleeder, and let the pedal back gently to refill the m/c without sucking fluid back up the lines. Do this eight or ten times at each caliper and you should be OK. If you have a residual soft caliper, try a power bleed using a power bleeder. Your one big problem will be frozen bleed screws and m/c fittings.

bleed according to sequences in the 700/900 FAQ at the calipers.

Steve, I don't think the FAQ covers pre-ABS bleed sequence for 240s.
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.