Brake flushing
Thread Starter
Member
Joined: Sep 2009
Posts: 142
From: Toronto
Brake flushing
Hi all,
I'm debating whether I should be doing this myself or pay my mechanic to do this on my next brake job. I looked at the instructions from the service manual and I've found a discrepancy compared to all the generic methods to flush found online.
Here are the steps in the manual:
In question are steps 3 and 4. To me, this method seems as though it would draw air into the system if the when bleeding from the valve the fluid in the reservoir empties. Online methods suggest using a syringe to suck out the old fluid in the reservoir, pour in new fluid, then go to each valve and bleed fluid until new fluid flows out all while ensuring the reservoir is not emptied.
Am I over thinking this, any thoughts?
I'm debating whether I should be doing this myself or pay my mechanic to do this on my next brake job. I looked at the instructions from the service manual and I've found a discrepancy compared to all the generic methods to flush found online.
Here are the steps in the manual:
Drain and Refill INFOID:0000000003895104
1. Turn ignition switch OFF and disconnect ABS actuator and electric unit (control unit) connector or battery
negative terminal.
2. Connect a vinyl tube to bleed valve.
3. Depress brake pedal, loosen bleed valve, and gradually remove
brake fluid.
4. Make sure there is no foreign material in the reservoir tank, and
refill with new brake fluid.
5. Rest foot on brake pedal. Loosen bleed valve. Slowly depress
brake pedal until it stops. Tighten bleed valve. Release brake
pedal. Repeat the process a few times, then pause to add new
brake fluid to master cylinder. Continue until the new brake fluid
flows out of bleed valve.
Bleed the air out of the brake hydraulic system. Refer to BR-15,
"Bleeding Brake System".
1. Turn ignition switch OFF and disconnect ABS actuator and electric unit (control unit) connector or battery
negative terminal.
2. Connect a vinyl tube to bleed valve.
3. Depress brake pedal, loosen bleed valve, and gradually remove
brake fluid.
4. Make sure there is no foreign material in the reservoir tank, and
refill with new brake fluid.
5. Rest foot on brake pedal. Loosen bleed valve. Slowly depress
brake pedal until it stops. Tighten bleed valve. Release brake
pedal. Repeat the process a few times, then pause to add new
brake fluid to master cylinder. Continue until the new brake fluid
flows out of bleed valve.
Bleed the air out of the brake hydraulic system. Refer to BR-15,
"Bleeding Brake System".
Am I over thinking this, any thoughts?
Member
Joined: Jul 2011
Posts: 128
From: VA
The way we bleed brakes takes 2 people. One to pump the pedal the other to open and close the bleeder valve. (You can stick a vacuum hose on the end of the bleeder if you like and catch the fluid in a container...we just used shop rags.) I would suck out the master cylinder, just so u won't have to pump out as much, then pump the brakes up (car not running). Start at the RR wheel. HOLD the pedal down and have the other person open the bleeder valve. The person in the car pushes the pedal to the floor and HOLDS it there until the other person tightens the bleeder back. Move to LR wheel and repeat. By now the MC will most likely be empty so fill her up with new clean fluid and go to the RF wheel and repeat. Then...u guessed it repeat on LF wheel. Rinse and repeat 
Go to RR and go all around doing the same steps again. If the fluid coming out looks dirty at any wheel, just bleed it 1 mo time. By now there should be clean break fluid all around.
Just curious, why do you need to flush them?
Go to RR and go all around doing the same steps again. If the fluid coming out looks dirty at any wheel, just bleed it 1 mo time. By now there should be clean break fluid all around.Just curious, why do you need to flush them?
Thread Starter
Member
Joined: Sep 2009
Posts: 142
From: Toronto
The way we bleed brakes takes 2 people. One to pump the pedal the other to open and close the bleeder valve. (You can stick a vacuum hose on the end of the bleeder if you like and catch the fluid in a container...we just used shop rags.) I would suck out the master cylinder, just so u won't have to pump out as much, then pump the brakes up (car not running). Start at the RR wheel. HOLD the pedal down and have the other person open the bleeder valve. The person in the car pushes the pedal to the floor and HOLDS it there until the other person tightens the bleeder back. Move to LR wheel and repeat. By now the MC will most likely be empty so fill her up with new clean fluid and go to the RF wheel and repeat. Then...u guessed it repeat on LF wheel. Rinse and repeat Go to RR and go all around doing the same steps again. If the fluid coming out looks dirty at any wheel, just bleed it 1 mo time. By now there should be clean break fluid all around.
Just curious, why do you need to flush them?
Go to RR and go all around doing the same steps again. If the fluid coming out looks dirty at any wheel, just bleed it 1 mo time. By now there should be clean break fluid all around.Just curious, why do you need to flush them?
I'd like to flush my 2009 (never been done before) because I will be changing the pads and am hoping that the flush will help fix my "mushy" peddle compared to other cars I've driven.
Member
Joined: Jul 2011
Posts: 128
From: VA
Thanks for the reply. Just to confirm, after each bleeder valve is done, are you to check the reservoir and fill to ensure it does not get empty (and allowing air to enter the system)?
I'd like to flush my 2009 (never been done before) because I will be changing the pads and am hoping that the flush will help fix my "mushy" peddle compared to other cars I've driven.
I'd like to flush my 2009 (never been done before) because I will be changing the pads and am hoping that the flush will help fix my "mushy" peddle compared to other cars I've driven.
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