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Yes! As the accumulator weakens, it will hold more fluid. So more the pumps of pedal, to evacuate. It also stores less energy. Since less nitrogen to compress. Which is rapidly depleted on first pump or two. So we get less help evacuating fluid as pressure drops off faster. Resulting less fluid on each pump of pedal. Also, booster motor runs longer and more frequently, since pressure drops faster. Result in shorten motor life.
The time to charge accumulator, is a test for air in the system. Found in the FSM, in bleed procedure. When accumulator charge time over 40 sec. We're directed to bleed again. Frankly, I don't see this as a good air in system test. Other than if air in certain cambers within the master unit. Since the brake lines nor the calipers, receive any of this stored energy, until pedal pressed. But it does give us clues, as to health of the brake fluid, booster system and master seals.
I found using Toyota brake fluid, to do a proper flush. Can reduce booster run time. So flushing is always first, in a working system with questionable fluids and long run time. Good fluid can also reduce pedal pump to evacuate accumulator.
Yes in your case a new accumulator may improve your braking, reduce pumps of pedal to evacuate and charge time.
When I grade a master. I use key indicators:
I do still, target components within booster assy and master. I do this more for research proposes, on my onw rigs. I take all the clues, see where they point. Number one clue, is condition of resevoir.
But for most, other than a proper flush. I recommend replacing the whole master assy, when diagnose is a master issue which result in alarms. Why:
The time to charge accumulator, is a test for air in the system. Found in the FSM, in bleed procedure. When accumulator charge time over 40 sec. We're directed to bleed again. Frankly, I don't see this as a good air in system test. Other than if air in certain cambers within the master unit. Since the brake lines nor the calipers, receive any of this stored energy, until pedal pressed. But it does give us clues, as to health of the brake fluid, booster system and master seals.
I found using Toyota brake fluid, to do a proper flush. Can reduce booster run time. So flushing is always first, in a working system with questionable fluids and long run time. Good fluid can also reduce pedal pump to evacuate accumulator.
Yes in your case a new accumulator may improve your braking, reduce pumps of pedal to evacuate and charge time.
When I grade a master. I use key indicators:
- Appearance of reservoir. Heavily stained, is indication brake Fluid not properly care for over life of vehicle. Black fluid, is shorter term indication. Both, a very bad sign. Which are the best clues, as to health of seals. It is also associated with clogged ABS screens, passages and valves.
- Is reservoir, slow to level out. Indicates clogged screens. Further clue as to bad fluid condition/health, long term.
- Number of Pump of pedal, to evacuate. Clue as to health of accumulator.
- Run time to charge evacuated accumulator. Clues as to health of Fluid, Booster system health and Seal with Master.
- Corrosion on brake control wire leads, inside the boots. Clue as to health of motors commutator (#1), brushes (#2) and electrical circuit within ABS unit (#3)
- Leaks, especially at master.
- Age.
- Miles
I do still, target components within booster assy and master. I do this more for research proposes, on my onw rigs. I take all the clues, see where they point. Number one clue, is condition of resevoir.
But for most, other than a proper flush. I recommend replacing the whole master assy, when diagnose is a master issue which result in alarms. Why:
- On the booster side. If we do I anything, that increases pressure. Very often, seal within master fails within 1 to 2 years, sometimes days. A seal that can't be replaced. So long term cost of repairs go up. Both in parts and labor.
- Reliability, of the number one safety device, goes down if the whole master assy not replaced.
- All to many DIYers, lack to skills and or aptitude, to do repairs safely. Sorry to say, many pros fit that description also.
- R&R the whole master. Is a one done. If then, care for properly. We can get 25 years or more life.
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