The Stovebolt Site Forums The Parking Lot Big Bolts Looking for help with brakes on a 1966 chevy C-50

I got most of my parts for my '56 dump at Napa. Several of the brake parts cross between years with minor differences. What fit mine were for 60's trucks, so they should have what you need if you get a good parts guy that's willing to dig.
Also, if you need it & they dont have the HydroVac available they did offer a rebuild service that's supposed to have a decent turn around time. The worst part of rebuilding one yourself is the pneumatic relay that makes it all work, it's a 1/2" bore piston with two tiny gaskets that tends to corrode into place rendering it inoperable.


Things you can do for free that will help:

1. take off the wheels and drums, make sure all your springs are present and accounted for, check for leaks on the slave cylinders, make sure all your adjusters are fully movable and of course that your shoes aren't trash.

2. Put drums/wheels back on, & while it's in the air adjust the brakes while turning the wheel untill it just starts to drag. Pump your brakes a time or two to center the shoes and try adjusting it out a little more. It shouldn't be dragging much, back it off if needed. It's also a good idea to recheck the adustments after a short drive as the shoes tend to shift to center on the drum better that way. The smaller the gap, the less fluid needed to engage.

3. Check function of HydroVac: First look at he vac-lins coming off your manifold all the way to the HydroVac, make sure they are intact and connected. Pump your brakes a bit while the truck is off, turn on the engine while maintaining pressure on the brake, your foot should go down a bit. If the truck was just running you should be able to turn it off, press the brake and hear a chuffing sound from the HydroVac once or twice(assuming your vac-lines and check valve are tight). If it doesn't, skip the next step. If the HydroVac isn't working you can still stop if you've adjusted everything and bled the brakes, they are built with a bypass valve just for that purpose.

4. The HydroVac has a large can on one side with 4 J-bolts. You should be able to loosen those bolts and remove the can. Clean the interior and seals, wipe inside with a good air-tool oil if you have any, 3-in-1 orsewing machine oil will do if you have to. Put it all together (with the small plug hole on the end on the bottom side), remove the small plug and add about 1 TBSP of air tool oil in the hole & replace the plug.

5. Bleed it! (OK, so this one requires buying fluid, so it's not a freebie) Start at the HydroVac, there should be two bleeders, one on top of the valve housing and one on top of the very end where the line/s come out, bleed in that order. From there follow the line forward to your closest wheel, then do the other front wheel. Then follow the line aft and do your closest wheel & if it has dual wheel slaves start with the one closest to the fluid line 1st. Then do the same with the other wheel and you're set. Of course remember to bleed till you get clean fluid out & keep the resivour topped or you'll suck air & have to do it all again!