1969 Kenworth Dump Truck. Not much movement in brake pedal. Does not appear to have air to the pedal. All other air works fine.

Are you draining water from the air tanks. There should be small taps on the bottom of all air tanks. Locate these and open slowly when system is under pressure. Make sure you close them when finished.

Ace Manufacturing - Clutch Brake Training Video - YouTube

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Jan 20, 2012 - Uploaded by usmadeclutches
Ace Manufacturing compares clutch brake options and and installation tips.

clutch kenworth 2007 suite 2 - YouTube

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https://www.youtube.com/watch?v=0JWtd2orTwQ
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How To Replace Brakes On A Dump Truck (HD) - Duration: 19:13. by W.C. Black and Sons, Inc. 181,172 views ...

A Diesel Truck Clutch replacement - YouTube

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Air GOVERNOR - YouTube

? 3:45
www.youtube.com/watch?v=9Vb32PL1PVU

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An explanation of how an air governor works in the truck airbrake system. Created by the School of Motive ...

bendix air brake compressor governor ... - YouTube

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HOW TO REPLACE AN AIR GOVERNOR , AND COLD START OF THE INTERNATIONAL DUMP TRUCK. ... BENDIX AIRBRAKE COMPRESSOR GOVERNOR REPLACEMENT , AND COLD START ! ... Don't like this video? ... Brake AdjustmentTraining Video - PetroWest - Grande Prairie Alberta - Duration: ...

low pressure switches can be mounted at the air tanks ,on the line from the compressor to the tank next to the tank or at the foot valve air pressure line in to the foot valve.

air in line ,need to have brakes bled...

didn't think something that old had a hydro clutch but some clutches sare the res with the brakes

Indicates air still in the system. I suggest that you start at the master cyl, remembering to keep it full during & after each attempt at bleeding the system and to only fill it by using a funnel & allowing the brake fluid run down the side to eliminate new air being put into the system.

Bleed the master cylinder first by loosening those brake lines while someone has pumped up the system & is holding the pedal to the floor. Make sure your assistant is not releasing the brake pedal before you are tightening the lines each time after bleediing the system, and that all brake pedal movement is done slowly, especially releasing the brake pedal. It causes fluid to rise into the air, bringing air back into the fluid.

Next, go to the farthest brake away from the master cylinder & bleed it, working yourself to the next farthest until you finish with the closest brake. This prevents air from switching lines on you during the process.

If there are no leaks & you have followed this method, there shouldn't be any air in the system & your brakes should be good.

Double check inside the truck to see if there is brake fluid coming from the new Master cylinder behind the brake pedal, that indicates the new seals didn't seat properly.

good luck

you still have air in the system you need too bleed it some more

this noise is caused by a defective power brake vacuum booster, (big round thing behind the master cylinder) the diaphragm is leaking vacuum.

My vote would be the Master Cylinder.
I had a truck sit for 4 years. After getting running again, it did the same thing you're describing. No brakes. I ended up replacing the Master Cylinder to fix the problem. Just make sure you bleed the system real good.