Hi all,
A strange thing that someone on here may have experienced,... and have hopefully found an answer.
Firstly, I have plenty of experience with brakes and have bled many systems before, but this one has me stumped. It is an all drum system, so that is different, but the principles for expelling air surely have to be the same!
I decided to replace my braking system completely on Mini Mayfair, after the brakes were failing,... going soft. The old system looked tired and there was obviously fluid leaking from one or two of the wheel cylinders.
I have now replaced everything on the system, the pipes, master cylinder, brake limiter valve, springs, all connectors, washers, wheel cylinders, bleed screws,... the lot (from Mini-spares). i have now completed this task, but now I am still having very similar problems to before! I have used new brake fluid on each occasion, and have used a one man Gunson bleeding kit connected to a tyre to push the fluid through the system into a jar with aid of a one way valve bleed pipe.
After opening the bleed screws in correct sequence, the system is seemingly flowing free of air bubbles. Yet after a day or two of driving the peddle starts to drop and there is now no pressure left.
I have bled the system three or four times thinking that this time the pressure was up to scratch, and all balanced and cannot see any leaks coming from anywhere on the system, only to find a day or to into driving the peddle slowly dropping.
There are no puddles or visible wetness on any joints. This must mean air is getting in, or there was still air trapped that is taking its time to move elsewhere which has an effect on the system.
I am worried that the new master cylinder is faulty, only because it was a bastard to put in, the room in the footwell for putting in the retaining split pin through the clevis pin was one of the fiddliest things I've ever experienced. This is worst case scenario, so I will ignore this until all other possibilities are pursued.
I have followed the manuals bleeding sequence, I have even tried tightening up all the brake adjusters, bleeding, then backing off the adjusters as some have advised on other sites.
What to try folks?
I am a sod for getting a job done and I do not want to give in and 'take the car to a garage'.
I am sure many of you may have had similar experiences, there must be something I am missing. The fact that it takes a day or so to fail could be telling, but offers no obvious resolve, like a puddle on the floor!
Any suggestions...
thanks, Jim