A friend put dot 3 in my master cylinder to bleed the brakes while I was gone. I use dot 5, so I flushed it out and chased it with denatured alcohol as described on a Corvette site. Then I learned I may have damaged the seals' I'm replacing all the cylinders. Blowing out the lines and putting new Dot 5 in. What about the residual valve? Is there any rubber in it? Where do you get a new one for all drum brakes? It's confusing on the web. No proportioning valve, right?
I think if these cars had "residual valves" from the factory they are built into the masters Cylinder? I can't think of there being any discrete (separate) valves for this in a drum brake car? Are you replacing the master also?
Yes, a master and all 4 wheel cylinders. I have new braided lines and eliminated the rubber there. I'm hoping there is nothing to be damaged if my car only used a residual valve or a distribution block. I just don't know what is inside them.
Will a master cylinder for disk brakes (with bleeders) work on my drum brake system? It has equal fluid pots and lid domes.
Gary, if you have a '67 chassis manual, there is a great description and some cutaway pics. There is a 'check valve' in the master cylinder on drum applications. It's purpose is to maintain 8-16# of pressure in the lines and wheel cylinders in static conditions..... this keeps pressure on the wheel cylinder seals to keep out air and prevent fluid loss (I just learned this!). I don't think there is rubber in the check valve. You may be able to remove it/them to inspect it. It's not used on disc brake circuits. The distribution block only has the piston for the brake warning switch. If there is a pressure loss in the front or rear, the piston moves and sets the dash warning light. I doubt there is any rubber in it.
DOT 5 with front drums? Seems like overkill. I converted to front disc, and get good pedal with DOT 3.
