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

I have a 1966 chevy C-50 dump truck... I need help with the brakes it has a Air thing under the driver side of the cab that deals with the brakes and plus a Master cydl. anyone know what it is called are where I could get parts for the Air thing.... and I need to know where you can buy parts for these big trucks.... Thanks alot guys...

the air thing most likely is the hydravac. how do you know its not working? i buy the majority of my stuff from napa.

Well I have to pump the brakes everytime I get ready to stop it.... I need to find somewhere where i can buy body parts and stuff for it......

Have you bled the brakes?

well i just bought the truck like a few months ago... im going to do that this week and if that don't help them it has to be in that something..... Does anyone know where I can buy the buy panels for a 1966 c-50 dump truck???????

Hy chevyman_1960-19, make sure you adjust the brakes up before you bleed them. Many parts can be purchased at Napa, and other suppliers, if you don't have a manual for your truck, try and find one, it will be invaluable, good luck.

I have looked for 1 and I can't find a manual for a 1966 chevy c-50 dump truck...... So how do I know when I got them adjusted right???? Ill Post some pics of the air thing and then truck and my other truck i got and thats a 1963 chevy pickup C-10....

Chevrolet didn't make the dunp body, so your looking for the big truck service manual that includes the C-50 Series. It may cover C-40 thru 100 Series trucks. You could also look on eBay for a Motor's Truck Manual from the mid 60's, they can be a good resource as well.

The "air thing" is called a "Hydrovac" and it's a vacuum power brake booster. They are still available rebuilt from NAPA.

If the shoes are to far away from the drum you won't have enough fluid in the master cylindar to make contact with just one push on the pedal. My 1957 Fire Engine has an ecentric bolt with a nut on the back of the backing plate located at 3 and 9 o'clock. When I rotate the nut if moves the shoes closer to the drum. Adjust them so there is a little bit of drag with the tire off the ground and your spinning the wheel by hand.

Good Luck!

Mike B

it does sound like you need to adjust the brakes. does it stop well? if it does, an adjustment might get you by for a while. tear it down later for a brake job. it probably needs it.

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!

Thanks Mike B.... Ill have to try that..... Chevy13man.... thanks man..... Freq2002 thanks that helps me out alot... I never knew you had to bleed it are anything.... So when I go to order the parts are the whole thing it's called a hydrovac... Does any 1 know the size hose that runs from the intake to the hydrovac.... The truck has not been ran over 9 yrs but I got it running and now the breaks does not stay up on it you have to pump.....

I also have a 1963 chevy c-10 that i can not get to go into gear... Even when I push the clutch in it will not go into gear... but if i start the truck in gear it will move even with out the clutch leakage on it.. what could be the problem there...... Tanks alot guys yall are being alot of help.......

Hy chevyman_1960-19, it sounds like the clutch disc is stuck to the flywheel. If you can lock the brakes or place the truck against something substantial [a tree or strong building], wedge or hold the clutch pedal down, and try to start the truck, this may break the disc free, good luck and be careful!

The HydroVac lines should be a combination of flex & hard lines. I fiddles w. a '66 in a junkyard a while back and the brake system was pretty similar to my old beast. There should be a large flex line going from your intake manifold to a fitting on the firewall where the check-valve is mounted, then a hardline down the firewall and under the truck to the HydroVac. The should be another soft line coming out of the HydroVac that goes to a small air filter, dont know where that would be mounted on your truck tho.
The inner diameter on my soft hoses is 1/2" and the hard lines are around 5/8", my rig is a bit older, but you can see the lines in this photo as the blue flex line and the check valve and hardline on the firewall.

On your clutch issue, you should get under there and eyeball your linkage for too much play that wouldn't allow the clutch to disengage, and pull the inspection cover off the bottom of the bell housing and see if your clutch fork and throwout bearing are in working order as well. Idealy you should have enough play that the T/O bearing doesn't touch the presure plate fingers, and when the clutch is depressed you should be able to reach in the gaps in the side of the plate (assuming yours has inspection gaps/holes on the edge) and wiggle the clutch disc.

Thanks guys yall are alot of help......

How do I post pics on this site???????????

see here .... need to have them hosted elsewhere

Bill

3B what a clever idea,I couls see that working!

I got the clutch undone... thanks for all the help......

I just got my new hydrovac booster from them brand new for my 66-67 C60 dump truck ask for Rick when you call and tell him Rick from sacramento Ca told you to call him his number is 404-659-8722 he's a great guy helped me a bunch so shoot him a line he will hook you up.


Rick
Sac, Ca