[Don K]

I just converted my '70 Chevelle Malibu from manual 4-wheel drum brakes to power front disc/rear drum brakes. The car has the original distribution block located on the frame rail down by the header on the driver side. I can't get fluid to the front brakes and I've narrowed the problem to the distribution block. Does the original block need to be replaced with something like this for the brakes to function properly?

Or do I need to eliminate the original distribution block and replace it with something like this that mounts to the master cylinder?

Please help!

 

[Delta]

I believe you will have to get rid of that distribution block since it was for drum/drum. I got disk/drum and have the following distribution block on mine.This mounts on the frame.

http://inlinetube.com/Prop Valves/PR-107.htm

As well as this hold off valve. This mounts on the right side of the Master Cylinder.

http://inlinetube.com/Prop Valves/PR-115.htm

And these lines to connect it.

http://inlinetube.com/Preformed Lines/Chevrolet A-body 68-72/Brake Lines/CHB70F1.htm

Last there is this other smaller distribution block that mounts to the rear crossmember on the drivers side.

http://inlinetube.com/Prop Valves/PR104d.htm

If you use that last item then you'll need this 2 piece brake line.

http://inlinetube.com/Preformed Lines/Chevrolet A-body 68-72/Brake Lines/CHB70M1.htm.

 

[Va72Chevelle]

I don't know if you need all of those valves - it will depend on how much of your old lines are usable (for example, your rear line and the distribution block on the rear axle should be good). My conversion kit came with what is called a proportioning valve that mounts to the master cylinder which feeds the front and rear lines. Sine the valve is no longer on the frame, you'll also need to rig something for the lines, either new lines from the proportioning valve to tie into the existing lines or new lines entirely.

I went with new lines. Now if I can figure out which line goes where. Not to which wheel but how they are routed next to one another as they branch out of the valve.

 

[myrusty66]

u shld just need the correct proportioning valve. and maybe the rear splitter depending if you trust your old one is not clogged up. inline tube is a great source for parts and info, give them a call and they will hook you up. they are in mi as well, shelby township.

 

[Jack Action]

I believe this thread is related to this one.

First of all, start at the base. You seem to have checked if fluid came out the m/c. If you have one, check if fluid comes out the metering valve. Maybe you plumb it the wrong way (It is a one way valve)? check if there is no obstruction in all the brake lines leading to the distribution block.

To check your distribution block, normally a few stomps on the brake pedal - while a rear bleeder is open if needed (to simulate a rear leak) - should «reset» your distribution block. Normally your warning light should be on, like it was at first, but maybe it is burnt (check it by grounding the wire connecting to the distribution block).

At worst, you can remove the front brake line and push the internal piston to center it.

If there's still no fluid coming out it's probably bad (internal leak or something).

As for your options to replace the actual system for your conversion, read this post. The system described by Delta is the OEM disc/brake and both the valves mentioned in your post are the combination valve of the '71 & up model (although they might be some internal difference for disc/drum or disc/disc application). It doesn't matter whether it is beside the m/c or on the frame rail. You don't «need» this valve, it is just a cleaner set-up (although the plumbing and electrical connections are all different from what you already have).