It seems at least one of your master cylinder washers is faulty. Is the fluid up to proper level? (Even if it is the master cylinder washers could be faulty).
The 'other reason' point seems more valid. Contrary to what most people think, retooling the disc isn't as necessary and shouldn't be done so frequently. Although there are different lines but they are not radial and any new pads would bed-in to this same pattern. The performance would not be like-new but would be consistent. Not at all like only when A/C is on the system will act up.
The search function doesn't properly work. Even if I know some thread and write its title in entirety the link shows up on 2nd page.
Anyhow I'd advise a complete brake system overhaul. Doesn't cost much and the results are awesome. Here is the cost breakdown for brake overhaul of a cultus I got done in January.
- Brake pads (front), Nippon (semi-metallic: carbon w/ steel filing), Rs. 650/-
- Brake shoes (rear), MK Kashiyama (organic: leather), Rs. 650/-
- Washers for pistons in rear drums, Ultima, Rs. 80/-
- Washers for master cylinder, FIC brand (also called master cylinder half kit), Rs. 180/-
- Turning of drums, Pervaiz lathe works, Rs. 150/-
- Mechanical work, Akram autos, Rs. 700/-
- 2 nos. boots for one of the caliper pins (front), incl. in labour charge.
- Some small globs of grease, 3 brand, incl. in labour charge.
- STP brand brake oil (I had a new bottle and brought with me).
If you also consider this overhaul, you'd be getting it done within Rs. 3000/-. (In fact you may spend some what less because when we got the system disassembled a lot of faults became visible which were out of routine maintenance, e.g. one of the rear-left pistons was jammed with rust, one of the front-right caliper pins was jammed with rust, and all brake pads and brake shoes had been consumed up).
In this overhaul specially, when all the work was done and bleeding started the mechanic noted that bleeding oil wasn't coming out in a squirt. It was just dripping. So we rushed to get the master cylinder half-kit to get it overhauled and found out one (out of 4) washer had swollen and was leaking pressure. And although the braking felt fine before too, after the overhaul it was nothing like Suzuki.
Based on this experience I feel you people have a problem with the master cylinder.
One more problem that arises with power brakes is that the vacuum pipe running from intake manifold to master cylinder gets frayed or develops a leak from where pressure is lost. If getting a replacement get a high quality one otherwise under vacuum the pipe will squeeze inward and you'll feel no power-assistance.
