I would like to share my experience of brake trouble with those of you who have old cars like my 1988 Toyota Corolla. I am doing so that you do not have to go through needless expenditure.
It started with the front disc pads wearing out after 7,000 kms. The second time I had to replace them after only 5,000 kms. I could hear squeaking sounds from the front of the car, and I felt that the pick of the car was not good. Fuel mileage had come down to 10 kms/litre from 12 kms/litre. I could sense that the front disc brakes were releasing heat after driving a few kilometers. The water temperature gauge would approach the red zone. At the start of summer the engine would run even hotter. And after checking with friends who are more experienced than me, I bought the front disc pad seal kits. I asked the mechanic, to whom I normally go to, to the change the seal kit. He removed one of the brake pistons and found it to be in good condition. He said there was no need to change the seal kit. So I returned the seal kit. Since I also saw the piston to be in good condition, so I felt confident that the problem was not with the front brake pistons.
However, all the problems noted above continued. As the engine continued to run hot. I was scared that the engine would require overhaul if it continued to run hot. The last time I had the engine overhauled was in 1997. I was also concerned that the clutch plate would wear out because of excessive load. During this time, the top radiator hose and the heater hose leaked due to high water temperature.
After going through all these hassles I got fed up and told the mechanic to change the front disc pad seal kit. After driving about 3 kms from the workshop, I noticed that changing the seal kit had no effect. The pick of the car was just the same as before. Out of frustration I referred to the Corolla shop manual to see if I could get any help from it. At one place, it was mentioned that the seals in the brake master cylinder could be worn out. I then went to the parts shop and I asked them for the seals and these I took to another workshop to have them fitted. The mechanic’s advice was that replacing the seals was not advisable as the brakes would not work after 3 hours. So I went back to the shop and purchased the brake master cylinder. The mechanic replaced the brake master cylinder and also adjusted the rod so that brake pedal play was correct. Since then the brakes have worked OK, the engine has not overheated, the pick is better and the fuel mileage has gone back to 12kms/liter.
Sometimes even good mechanics are not able diagnose the actual fault so it would be advisable to get a second opinion and refer to manuals and literature online to get the correct diagnostics which in turn would save your from a lot of hassle and wasting money. I hope that others, after reading about my experience, would not have to go through needless expense and mental tension.