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GS Hog
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Discussion Starter · #1 ·
Pressure bleeding brake system.

Does anyone know how much pressure is required when pressure bleeding the G2 brake system?
 

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I'm stumped

LegendGS, pressure bleeding? You mean you actually have the injector/ bleeder and the UPA for the master cylinder? I know that a good injector / bleeder usually pressurizes at like 125 to 150. Costs money.

Now, on the other hand....

I built a bleeder that uses suction to draw the fluid in the reservoir through the lines and out the bleeder nipple for mega cheep. Spent $10 and have bled both my cars, my neighbors and my best friends. Cheap, quick and easy - just the way I like my wemon!

KNLNGUS
 

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GS Hog
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Discussion Starter · #3 ·
No, I'm actually looking at another unit that is meant for the DIYer. www.motiveproducts.com

They don't recommend pressurizing beyond 20 PSI as it could damage the brake system, but I'd like to know how much pressure is recommended for our cars.
 

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Hmmm.

From the looks of that garden / weed sprayer - it screws onto the reservior and you pump (up some pressure) then run around to the right rear and start yanking on the bleeder bolt. Looks like it would work just fine - quite well actually.

proffessional injector / bleeders are built to last and are designed to handle different jobs and pressurize up to (I believe) 150lbs. The idea behind an injector / bleeder is that you are at each wheel, squeeze the gun a bit, loosen the bolt, and squeeze the gun more. Fluid doesn't tricle or barely flow out - I rushes out. The dealers use the injector / bleeders.

MOST IMPORTANT THING HERE IS THAT YOU ARE LOOKING AT THE RIGHT METHOD!

I had to replace my master cylinder after bleeding the brakes using the pressure from the pedal. Well, sure enough - a month later, I started to loose pressure on the pedal. I believe it happened because I put undo stress on the seals in the master cylinder.

Good luck! Let us know how that contraption pans out!

KNLNGUS
 

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GS Hog
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Discussion Starter · #5 ·
Yeah, same thing happened to me when I had my brakes done at the dealer, execept that it didn't take a month. It went the very next day.

That's why I'm looking into alternative methods.

I read the user guide online and it states that the amount of pressure needed could be found in the service manual. Problem is that I looked at my Helm manual and can't find anything that mentions pressure bleeding.

I emailed the company and they told me to ask a tech, and that typically, Acuras use 8-20 PSI. Where in that range it would be, I have yet to find out.
 

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Roger, without specialized tools its a two person operation and ideally should be performed in a dry environment.

Basically all you need is a

10mm open/closed wrench
about 4-5 feet of 1/4 transparent air hose
catch bucket
24 oz of DOT 3 brake fluid

You will need to start at the rear passenger side - support vehicle - remove wheel - attach closed end wrench to the bleeder bolt - then fit the air hose to the bleeder nipple. Ensure the air hose travel upwards and (for instance) wraps through one of the coils on the strut for support and then downwards to the catch bucket.

Have a partner apply pressure to the pedal (not like a monkey though) in a "Pump and Hold" fashion. After your partner pumps the pedal you will see the caliper compress the pads onto the rotor, then you loosen the bleeder bolt a little and you will see fluid escape into the air line. You will notice that the fuild stops rising and your partner will notice the pedal draws towards the floor board. At that time, you tighten the bolt and them have your partner pump and hold the pedal again while you repeat this process. Repeat this process until there are no bubbles coming out of the line AND until the fluid looks clean. You want the fluid coming out of the bleeder bolt to look like honey (equal to new DOT 3 fluid).

Be sure to check the fluid in the reservior and top it off frequently before, during and at the end of the process.

You will perform the bleeding in this order

Passenger rear
Driver side front
Driver side rear
Passender front

DO NOT DEVIATE FROM THIS ORDER.

The bleeder bolts have a 7lb torque if you have a wrench - otherwise, just make sure they are tightned securely and that there is NO SIGN OF FLUID COMING OUT OF THE BLEEDER BOLT WHEN THE BRAKE PEDAL IS COMPRESSED before moving onto the next wheel. Do not overtighten the lugs (80lbs and in cross alternating fashion)

FYI, I started my car a couple of time during the process to help avoid cavitating the system.

I'm sure there are others that may have some to offer - and all advice is welcomed.

Good Luck.
 

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Roger, YES - this is true. You can damage the master cylinder. I do know that you greatly increase your chances if your partner is "trying to activate the ABS while the car on jack stands" if you know what I'm saying.

I have done this successfully (as many others as well - including those on this forum) BUT I was also unsuccessful on my last occassion also. My master cylinder did crap the bed on me last time - but I installed a new one master cylinder and fabricated a vacuum system which I recommend, then another guy on the forum found a website where this attachment replaced the cap on the reservior and you pumped pressure into the system that way - but i was a bit hesitant about that setup.

Good news is that I have a few master cylinders incase you or others need one - napa boxed, new reservior and cap w/ leads, do not charge tax, and do not want your core either.

Anyone else offer suggestions?

KNLNGUS
 

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A good indicator would be exactly what you just mentioned, shy of glazed rotors or glazed pads.

Look at the color of the fluid in the reservior and in the ABS reservior - does it have a redish tint or any other color besides clear? If so, chances are it needs to be flushed out because the properties of the fluid have changed.

Many people have "pumped" out the fluid in the system via the brake pedal with great sucess - just don't have someone work the brake pedal if you know they are not going to be responsive to your instruction. They are not trying to stop the car from traveling, they are just there to pressurize the system (with ease) while you loosen the bleeder bolt and then retighten. You do not want someone who will be an ignoramous that does not pay attention. I can't stand it when someone is listening to the radio - fiddling with the interior - reading a mag. Cripe, they should be there - attentive to your instruction and give the project the respect you deserve.

Have them press lightly and the fluid will come out. FYI, this project is not a difficult one - just one that requires patience and about or less than an hour of your time.
 

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Thanks for chiming in Mike - I do like the appearance of that contraption.

Roger, yes I did make my own brake bleader which I have used to syphon the fluid from the ABS reservior and power steering reservior also.

What I did basically was go to loes to buy 2 1/4 to 1/4 adapter and stuck one in the air inlet of a miniture gas tank. I then drilled a hole large enough to push the adapter through (just barely) into the gas end of the miniture tank. I ran air line from the bleeder bolt into the 1/4 adapter and then a second air line from the 1/4" adapter on the other side of the miniture tank to an air pump commonly used for aquarium applications. I also had to secure the hose onto the nipple with a zip tie because at first the pump was drawing air between the hose and the nipple.

I spent under $20.00 and have used it on both my legends, my neighbors vehicle, and a friend. Although my close friend did need a fluid change, I had to convince him cause I was so happy with my contraption.

KNLNGUS
 
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