This is an age old argument and I intend to address it completely, there is just to much confusion.
1. why I pulled my PM
I pulled the PM system for several reasons, most importantly is because it had an internal leak causing the motor to run constantly. I could have fixed it but then I thought, why would I want to keep somthing in my car that makes you scratch your head and post a thread to figure out how to fill the freakin resevuor. Also I don't want to keep a brake system that has the potential to fail and possibly lose braking ability completely in a car I have this much money invested in. I suppose if you have a trailer queen that needs to hold a ton of boost at the line, you should keep your PM. Then again, if you spent the money to have that 9 sec trailer queen there are better options then the PM. Also I have a rear mounted turbo and my MAF pipe butts against the PM's resevour cover. Should it nudge the cover and unseat it the result to the PM could be catastophic.
Misconceptions:
The first and most important some say is that vacuum systems won't hold boost. This is a load of crap, the vacuum system is an assist, it has its own vacuum booster which only uses the cars vacuum to charge it. Once charged it does not require vacuum to work, that is why it has a check valve. If it is not holding boost, there is a reason like bad proportioning valve, or air in the lines. That is unless you have a trailer queen that builds a ton of boost at the line and run's low 9's or so, and if thats the case then this thread is not for you.
Next, should you apply hard brake while under boost from a hard start you won't have any brakes...as Penn and Teller would say "Bullsh**". The vacuum system has enough stored vacuum for several hard stops. Even if there were no vacuum left you would still have the equivalent of manual brakes. Basically you can stop the car. If you can't stop the car something is wrong, ie: not properly bled, or bad proportioning valve. Frankly I can and have pulled the vacuum line off the vacuum assist and guess what...I can stop the car.
With thats said lets address bleeding the system, I can look up 100 threads and find 100 different opinions on bleeding the brakes. In the past weeks I have tried most of them. Below I have combined it all into a nice easy user friendly way to bleed them all by yourself.
1. Bleed the MC, I recommend some kind of vacuum pump, it's cleaner and easier but not necessary. You can power bled the Master Cylinder. But that will require 2 people. So since this is about doing it alone I won't get into power bleeding the MC, buy the vacuum pump its cheap and very usefull. Follow the instructions that come with the vacuum pump to bleed the MC, you can do it mounted in the car, you don't need a vise.
If you have not replaced the MC, or disconnected the brake lines attached to the MC, or let the MC drain. Then you don't need to bleed it...
2. Scoot under the car and mounted to the frame under the drivers side you will see the proportioning valve. This has a little nipple at the front that extends. The idea is to keep it from extending, the most creative and effective way I saw was to wedge something between it and the "A" frame. It just has to have enough tention to keep whatever you used from falling. I used a brass 90 degree adapter I had from my FPR. But you can use whatever works. Just be carefull not to wedge anything in there to tight or you will be buying a new valve.
3. Now you are free to bleed the rears. This is simple, you can crack the bleeder open then close it finger tight. Attach a clear vacuum line to it and put the other end in a jar. Open the valve and wait. It will eventually flow into the jar. When the flow is clear of large bubbles your done close the valve. Of course if your patience is lacking like mine, hook that vacuum line to a vacuum hand pump, charge it with about 6 cranks on the hand pump and open the valve, since it is finger tight you can use the hose itself to open the valve. Now you will see bubbles and old dirty fluid. When the large bubbles stop and the fluid is clean your done. The order is RR, RL, FR, FL.. after you finish with one check the levels. I drew enough on the rears to send it to minimum every time.
Hope all this helps..............
1. why I pulled my PM
I pulled the PM system for several reasons, most importantly is because it had an internal leak causing the motor to run constantly. I could have fixed it but then I thought, why would I want to keep somthing in my car that makes you scratch your head and post a thread to figure out how to fill the freakin resevuor. Also I don't want to keep a brake system that has the potential to fail and possibly lose braking ability completely in a car I have this much money invested in. I suppose if you have a trailer queen that needs to hold a ton of boost at the line, you should keep your PM. Then again, if you spent the money to have that 9 sec trailer queen there are better options then the PM. Also I have a rear mounted turbo and my MAF pipe butts against the PM's resevour cover. Should it nudge the cover and unseat it the result to the PM could be catastophic.
Misconceptions:
The first and most important some say is that vacuum systems won't hold boost. This is a load of crap, the vacuum system is an assist, it has its own vacuum booster which only uses the cars vacuum to charge it. Once charged it does not require vacuum to work, that is why it has a check valve. If it is not holding boost, there is a reason like bad proportioning valve, or air in the lines. That is unless you have a trailer queen that builds a ton of boost at the line and run's low 9's or so, and if thats the case then this thread is not for you.
Next, should you apply hard brake while under boost from a hard start you won't have any brakes...as Penn and Teller would say "Bullsh**". The vacuum system has enough stored vacuum for several hard stops. Even if there were no vacuum left you would still have the equivalent of manual brakes. Basically you can stop the car. If you can't stop the car something is wrong, ie: not properly bled, or bad proportioning valve. Frankly I can and have pulled the vacuum line off the vacuum assist and guess what...I can stop the car.
With thats said lets address bleeding the system, I can look up 100 threads and find 100 different opinions on bleeding the brakes. In the past weeks I have tried most of them. Below I have combined it all into a nice easy user friendly way to bleed them all by yourself.
1. Bleed the MC, I recommend some kind of vacuum pump, it's cleaner and easier but not necessary. You can power bled the Master Cylinder. But that will require 2 people. So since this is about doing it alone I won't get into power bleeding the MC, buy the vacuum pump its cheap and very usefull. Follow the instructions that come with the vacuum pump to bleed the MC, you can do it mounted in the car, you don't need a vise.
If you have not replaced the MC, or disconnected the brake lines attached to the MC, or let the MC drain. Then you don't need to bleed it...
2. Scoot under the car and mounted to the frame under the drivers side you will see the proportioning valve. This has a little nipple at the front that extends. The idea is to keep it from extending, the most creative and effective way I saw was to wedge something between it and the "A" frame. It just has to have enough tention to keep whatever you used from falling. I used a brass 90 degree adapter I had from my FPR. But you can use whatever works. Just be carefull not to wedge anything in there to tight or you will be buying a new valve.
3. Now you are free to bleed the rears. This is simple, you can crack the bleeder open then close it finger tight. Attach a clear vacuum line to it and put the other end in a jar. Open the valve and wait. It will eventually flow into the jar. When the flow is clear of large bubbles your done close the valve. Of course if your patience is lacking like mine, hook that vacuum line to a vacuum hand pump, charge it with about 6 cranks on the hand pump and open the valve, since it is finger tight you can use the hose itself to open the valve. Now you will see bubbles and old dirty fluid. When the large bubbles stop and the fluid is clean your done. The order is RR, RL, FR, FL.. after you finish with one check the levels. I drew enough on the rears to send it to minimum every time.
Hope all this helps..............
