Feedback on clutch
12-15-2015, 12:21 PM
#16
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To try to understand this correctly, this system acts like a vacuum brake booster? When engine is truned on, it create vacuum and assit the brake pump, when you shut it off, you still have some vacuum in the system so it might allow you to push effortless the pedal 1-2 or maybe 3 times, then it gets stiff because no more vacuum presence. I'm guessing the same theory should apply to our clutch system rather than vacuum, with hidraulic and the accumulator, so after engine is off, the clutch should be soft for about 2-3 pumped?
The accumulator is nothing more than a pressurized container, sort of like the air tank on a compressor. When the engine is on, the power steering/clutch pump is running, and it pressurized the lines and the accumulator. When the engine is running, the pressure is maintained in the system, even if you use the clutch. If the engine is turned off, the accumulator, as a tank, can supply enough pressure to assist the clutch action several times. The idea is that if you park the car for instance, turn the engine off, come back after a few minutes, and jump in and push down the clutch to start the car, it will be as easy as if the engine is running.If the car has been sitting for a while, say overnight or longer (depending on how well the accumulator holds the pressure), the pressure will bleed off and the clutch will be heavy. If you pump the clutch say 10 times with the engine off, you will also use up all the accumulated pressure in the tank, and the clutch will also get heavy - i.e. unassisted.
I cannot test it on my car either, like Basal Skull, I have also "gone manual".
Cheers,
Mike
12-15-2015, 09:23 PM
#17
Yes, but the opposite, it's not a vacuum it's pressurized. The accumulator is nothing more than a pressurized container, sort of like the air tank on a compressor. When the engine is on, the power steering/clutch pump is running, and it pressurized the lines and the accumulator. When the engine is running, the pressure is maintained in the system, even if you use the clutch. If the engine is turned off, the accumulator, as a tank, can supply enough pressure to assist the clutch action several times. The idea is that if you park the car for instance, turn the engine off, come back after a few minutes, and jump in and push down the clutch to start the car, it will be as easy as if the engine is running.
If the car has been sitting for a while, say overnight or longer (depending on how well the accumulator holds the pressure), the pressure will bleed off and the clutch will be heavy. If you pump the clutch say 10 times with the engine off, you will also use up all the accumulated pressure in the tank, and the clutch will also get heavy - i.e. unassisted.
I cannot test it on my car either, like Basal Skull, I have also "gone manual".
Cheers,
Mike
The accumulator is nothing more than a pressurized container, sort of like the air tank on a compressor. When the engine is on, the power steering/clutch pump is running, and it pressurized the lines and the accumulator. When the engine is running, the pressure is maintained in the system, even if you use the clutch. If the engine is turned off, the accumulator, as a tank, can supply enough pressure to assist the clutch action several times. The idea is that if you park the car for instance, turn the engine off, come back after a few minutes, and jump in and push down the clutch to start the car, it will be as easy as if the engine is running.If the car has been sitting for a while, say overnight or longer (depending on how well the accumulator holds the pressure), the pressure will bleed off and the clutch will be heavy. If you pump the clutch say 10 times with the engine off, you will also use up all the accumulated pressure in the tank, and the clutch will also get heavy - i.e. unassisted.
I cannot test it on my car either, like Basal Skull, I have also "gone manual".
Cheers,
Mike
That acumulator looks very close to what I changed in my e34 M5 for the rear SLS EDC shocks, when I took one appart and cut it in half I could notice it had a two chambers separate from a rubber membrane, maybe to do something with the pulsations.Anyways, good to know!