Tachometer fails at 2K to 3K RPM

[gordyzx9r]

Okay...I went out to the garage.

Pressed/released pedal 10 times (on the tenth it got real hard), with the ignition off.

Turned the ignition on and:

Brake light went off at about 8 to 9 seconds.

Motor stopped running at 17 seconds.

[gordyzx9r]

Well..it's looking like it's time to replace the whole Powermaster assembly.  It's seeping fluid from the base of the unit where it attaches to the firewal (master cylinder?)l and from the seals below the reservoir.  

I have a new one, completely assembled and ready to go on...just need to figure out if this is something I should do or if I should find someone else who can.  It's the bleeding of the system that I'm not looking forward too...

[Top Speed]

The bleeding is the hardest part.

[Recklessrob]

Bleeding is easy. Your rebuilt PM should've come with a Turkey baster like syringe.
That is used to force fluid into the pump supply holes. The rest bleeds like a regular brake system..

[gordyzx9r]

What sizes are the threads for the lines going into the Powermaster?

What size bleeder wrenches/flare wrenches are used for the bleeder screws?

[gordyzx9r]

Bleeding is easy. Your rebuilt PM should've come with a Turkey baster like syringe.
That is used to force fluid into the pump supply holes. The rest bleeds like a regular brake system..

I have never bled brakes before on anything...so this will be entirely new for me.

Questions:

This isn't the new brass proportioning valve is it?




Just to make sure I'm headed in the right direction...th is is the bleeder valve for the front brakes?



This is the bleeder valve for the rear brakes (above where the brake line is entering)?  What the heck kind of tool do you use to open that bleeder valve with!?!  



I saw a post on gnttype about using Russel Bleeder Valves, has anyone else done that?

[Recklessrob]

I think its a 9/16" wrench for the lines. I've personally never used the Russell bleeders, but have heard good about them. That is not the brass combination valve.
Those were never recalled on the GNs, just the Caprice wagons. Unless there is a problem, there is no reason to replace the cobination valve. Besides, the replacement was a brass valve that has been discontinued. I bought one of 4 that remained in the country from a dealer in South Carolina when I needed one a couple years back. I doubt there are any left now.

[gordyzx9r]

I think its a 9/16" wrench for the lines. I've personally never used the Russell bleeders, but have heard good about them. That is not the brass combination valve.
Those were never recalled on the GNs, just the Caprice wagons. Unless there is a problem, there is no reason to replace the cobination valve. Besides, the replacement was a brass valve that has been discontinued. I bought one of 4 that remained in the country from a dealer in South Carolina when I needed one a couple years back. I doubt there are any left now.

I found this reproduction while researching this.  I think Kirban's makes one too.  If this is a matter of it ain't broke, don't fix it...then I'll leave it as is.  

9/16" to open the valves?  Will a flare wrench work?  I've seen some folks say something about a wrench with a nipple on it for the rears?

[Recklessrob]

9/16" flare wrench for the lines at the powermaster. Front bleeders are 10mm, and rears are 8mm ( a 1/4 drive 6pt socket works fine if you don't have the fancy wrench)

[Recklessrob]

As for the combination valve, If its not broke, don't replace it. Its very likely that is the same valve that Kirban sells.

[gordyzx9r]

This is the fluid that came out...I'm a little surprised seeing as how I had all new SS lines, aluminum drums, S10 upgraded rear brakes, and a complete SSBC system up front.



Look at the gunk in the bottom of that:



Getting the pushrod off the brake lever was allot easier when the plastic retaining ring broke :phpbbt;



I was surprised how easy it is to take the whole thing out.



Bled the master cylinder...ble eding the rest of the system and putting the Russel speed bleeders on the rear.  Taking a break right now.

[Steve Wood]

Damn!  You work pretty hard!  

[gordyzx9r]

Damn!

[gordyzx9r]

Well, I used my handy dandy Craftsman vacuum tool to bleed the system and I think I've got her licked.  I haven't road tested her yet, but in the drive way I notice a pretty substantial difference.

[Recklessrob]

CONGRATS on making a substantial difference !!!  :supz:

 :rofl;  As you now know, its really not that hard to do.