Brake Bleeding issues

[GSTOY]

I replaced both front calipers this weekend, and for the life of god, I can't get the thing to bleed properly. I'm using a mini vac to pull a vacume to get the air out of the line, but I get nada.

Thank goodness for the web, I figure since these powermaster system are so special, maybe I'm doing this wrong, sure enough, I'm supposed to push in on a pin that's located on the proportioning valve and find a way of holding it...ok...I find it but the pin won't push in, then it does and I'm not ready to hold it, so it pops back out and now it won't go back in and the brass tip broke off...)*&%#!!^*() What the heck am I doing wrong, or would the concensus be that the proportioning valve was bad, causing all the grief?

I should give some background on this. The car sat for I think 6+ years. The front brakes were working, but the rotors were shot, and the calipers were sticking.

Where can I find a proportioning valve for a 87 GN? Also, where can one find the rubber cover that goes on the master cylinder?

Thanks,

Steve

 

[CS99]

Look at the calipers. The bleed screw has to be ON TOP OF THE brake line. You could have the calipers switched side to side. If the bleed screw is not on the top, you will never get the air out.

 

[BlackMetal]

I never heard about that pin on the prop valve.

 

[bosted86]

dont need to push that pin in. did you try bleeding the old fashion way? turn car on(dont start) and have someone push the pedal and you loosen the bleeder. my original proportioning valave went bad and i replaced it with a brass one. all is well.

 

[GSTOY]

The bleeders are located on the top of each caliper. As for bleeding them the old fashioned way..that's next. I'm single, so I don't have a extra body, so I'm inviting my friend over

Just as a FYI taken from the TR website:

How to Bleed the PowerMaster brake system

To bleed the PowerMaster brake system properly, perform the following procedure (the Hydroboost system has a unique procedure for bleeding the pump similar to a power steering pump ... see your chassis manual for Hydroboost instructions):
Bleeding should be performed in this order:

RIGHT REAR
LEFT REAR
RIGHT FRONT
LEFT FRONT

1.Get a friend who doesn't mind repetative tasks! Your friend will be asked to depress the brake pedal slowly and SMOOTHLY while you open and close the bleeder nipples.

2.As already noted, ensure that the pressure has been released from the system.

3.Clean the top of the master cylinder and then remove the top cover. This prevents dirt or moisture from the cap dropping into the brake fluid.

4.The spring loaded plunger on the front of the proportioning valve should be depressed while bleeding the system. The valve is mounted on the inside of the driver's side frame rail.

5.A "C" clamp or piece of wire and chunk of wood can be used to hold the plunger while bleeding the brakes. The plunger is normally at the "in" position and the "C" clamp (or wire/wood) is used to hold the plunger in this position.

6.Attach a bleeder hose and dangle the end into a clear container.

7.Have your friend lightly depress the brake pedal (with ignition ON). While this is done, open the bleeder nipple and observe the fluid flow.

8.Have your friend slowly push the brake pedal to the floor and then hold it there until the fluid flow stops. Close the nipple and THEN tell your assistant to release the pedal. This is important, since releasing the pedal too early will suck air back into the line.

9.Allow your friend to release the pedal. Repeat steps x and y several (10-15 times) until the fluid flow is steady and bubble free. ALWAYS BE SURE THAT THERE IS FLUID IN THE MASTER CYLINDER RESERVOIR! Never let it go dry, or you'll have to start all over (and I'll guarantee that you'll be worse off than before).

10.Tighten the nipple and clean up.

I too have never heard of depressing the button, and I like to do my research before posting a Q, so I followed directions LOL Well, it's not working, so I'm going back to old fashioned basics.

Steve

 

[bosted86]

i know it says that in there but you dont need to with the powermaster. i didn't do it with my brakes and they are working great (knock on wood).

 

[imjoesnuffy]

Do yourself a favor and buy the speed bleeders. Cheap, fast and they work. $7 for 2 at Autozone I think. I kept messing it up the old fashioned way, bought these and now can hold over 15 psi on the foot brake.

 

[zeus87gn]

I have never messed with my prop valve when bleeding.
I prefer not to pump bleed a P/M. Especially with the key on.
IMO, those procedures are out of date.
The order you bleed the wheels doesn't matter - to my knowledge.
I still bleed them old school order - RR, LR, RF, LF.
My brakes work just fine.

You may have to pump them once or twice if you can't get a vacuum pump to get the fluid through. You probably have a blockage that it can't get out from sitting for so long. But if you do pump them, leave the key off (pumped down). The fluid can get churned up and the P/M won't work well with air in it. Not to mention your running the motor when you don't need to.

I have some procedures that might help you.
See link in my sig.

 

[BlackMetal]

Do yourself a favor and buy the speed bleeders. Cheap, fast and they work. $7 for 2 at Autozone I think. I kept messing it up the old fashioned way, bought these and now can hold over 15 psi on the foot brake.

I've been considering those for a while. We'll see how it goes without them but if I can't get a decent pedal I might buy those.

 

[TheYak]

Recently i've just fixed mine after having bleeding issues, couldn't get the air out of the lines no matter what i tried. I ended up separating the resevour from the slave cylinder and checking the rubber groomets. When i looked i was suprised to see that there was alot of junk built up in there and was allowing air to get sucked in to the system. So about $5 later for new rubber grommets (Kirbans) i was back in business with a kick ass powermaster

Just something i thought i'd share that is easily overlooked, good luck

 

[zeus87gn]

Recently i've just fixed mine after having bleeding issues, couldn't get the air out of the lines no matter what i tried. I ended up separating the resevour from the slave cylinder and checking the rubber groomets. When i looked i was suprised to see that there was alot of junk built up in there and was allowing air to get sucked in to the system. So about $5 later for new rubber grommets (Kirbans) i was back in business with a kick ass powermaster

Now that's the kind of success stories I like to hear!

 

[GSTOY]

After having a friend over tonight and bleeding the brakes the old fashioned way, life is good again.

Steve