68 K10 Brake Question

[Dave K.]

Drums all the way around, no power. I installed new wheel cylinders and master but didn't replace the distribution valve (I believe this set-up had one of these and not a proportioning valve correct?).

So I went to bleed the brakes and I'm getting nothing out of the rear lines so assuming the distribution valve is seized up. I looked on Napa and couldn't find anything that jumped out as the same.

Any ideas on the correct part and source? Am I interpreting the lack of fluid to the rear correctly? When I can crack the line at the valve I'll probably know more but right now it's a bear to free up and I don't want to have to run a new one if I can keep it original (read trying to minimize the inputs here right now and the lines are as noted externally very solid!).

[Dave K.]

Here's the valve in question--anyone have a source for it? 1968 K10.... drums all the way around. Thanks, Dave.

[jocko]

Dave, asuming master cyl is bench bled, I'd keep trying for a bit, it takes an annoyingly long time to get fluid pumped and air out after all the new parts you installed. If there is fluid in the res for both front and back, a failed distrib block could be causing your problem, but so could air in the system. Was your dash brake light working correctly beforehand (on momentarily at start, then off)? Is it on now? If working before, but on now, try a few HARD stomps on the pedal to reset the valve to center. Sometimes it just comes down to replacing the valve when all other clues come up dry, but if all was good with the valve before the swap, it's probably fine now too. If light is off, but works, I'd focus on system air. If you need a valve, LMC should have them, they are not inexpensive. You are correct - your truck has a distro block only in 68 - and a safety feature. Loss of pressure on one circuit causes the valve to isolate the opposite circuit so you don't squirt all your brake fluid out trying to stop. 2 wheel brakes are not as good as four, but much better than none. Keep us posted!

[Dave K.]

Thanks for the input. I'll have to check the light issue as well as the other items noted. I know I have possible electrical issues because now when I stomp on the brakes both turn signal lights come on! Also, I know only the front left brake seems to be working well--it pulls heavily to the left and still no juice coming out of the rear wheel cylinders (brand new). I'm going to pull the right front apart again and see what's going on there.