I finally got the wife out in the garage last night to help me bleed the brakes. ( I need to just break down and by a Motive Power bleeder) but after cracking the rear, inner bleeder first, I could not get any fluid to flow... I remembered that the proportioning valve may prevent this so I also cracked open the front wheel bleeder and still no fluid to either caliper. The MC is new and I did bench bleed it before installing it on the car. All new stainless lines, hoses and calipers. I can only think the Proportioning valve is stuck and needs centered, but I could be wrong, hence my need for your advice...
As the bleeders are open and the pedal is being pumped, I can hear air (Can't really feel it, but hear what sounds like air) but no fluid is flowing... Help!!!

 

Your '69 does not have a proportioning valve -at least not from the factory. You have only a distribution block and a pressure differential valve for the brake warning light. To center the warning valve you close the bleeders and put hard pressure on the pedal. This will usually center the valve. Of course, this works only if there is hydraulic pressure to center the valve and it's equal on both sides of the valve. If it doesn't, you can open the bleeder of the side that is unaffected (if a rear brake hydraulic failure caused the valve to move, you'd open a front bleeder) and slowly press the brake pedal. But the valve does not affect fluid flow regardless of its position and it would never affect both sides of the valve. If it did, then a failure on one side would take out your whole brake system.

If you are not getting fluid from the bleeders there is something wrong with your technique, your parts, or your installation. Ruling out parts as the problem since you replaced everything leaves you with only your bleeding technique or an install problem. The install should be pretty intuitive so unless you managed to do something like mount a caliper with the bleeder on the bottom (not on these parts, though) you are left with a flaw in your bleeding technique.

First off, you do NOT need any special equipment to properly bleed the brakes. It can be done by conventional methods (pump-hold-bleed, vacuum, or even gravity) with the same outcome as a pressure bleeder. I use a small vacuum pump and it comes out fine every time. I suspect you have not adequately bled the master cylinder, which is the usual cause of difficulty in fluid flow at the caliper. You will probably get some good perspective by searching this forum for master cylinder bleeding technique. I have my method, but there's more than one way to do it.

 

have you already read/seen this?
http://forums.corvetteforum.com/c3-t...fo-please.html

 

With all new lines and no pressure it takes a while to get that fluid to the rears. Crack the left rear inner and come back after a beer.
Chris

 

Thanks for the information, and yes I have read the post that goes into excellent detail with regards to bleeding the brakes. It's one of the best posts I have read on any forum.

I did follow those instructions and bench blead the MC, using old lines sealing the end. My new MC has bleeder valves so it was simple and the plunger was solid and would not move when I was finished. However now that it's on the car, one item that that is concerning to me is that when I pump the brake pedal, bleeders closed, I get some air bubbles comming back up throught the brake fluid in the MC. Not sure if this is just traped air with the plunger being depressed in the MC with no where to escape or not... I am no mechanic but have bled brakes plenty of times before and using the same technique, perhaps it's like golf, even a bad technique will provide results just not good... any suggestions?

 

If you have air bubbles in the master, then there is still air in the master. I found the easiest way to bench bleed the master is in the car. you can run some old lines from the outlet ports back into the resevoir, then pump the pedal until no more bubbles. You do have to jack up the rear of the car until the master is level.

Here is the setup I used on mine and it worked great.