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Understanding air brakes

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Good day fellas , I may be on the wrong form but I hope you guys will still help me . I just bout myself a 74 chevy c65 single axle dump truck.  She runs drives stops and dumps so a great little investment.  Stopping She slightly pulls to the right . So I'm wanting to go over them replace brake chambers, adjust slack adjusters just get the system to stop on a dime , or at least straight . Can anyone point me to the right literature on this style of system? I look up air brakes and I get lost . I left what I imagine is my e brake on for for about a mile and I seen it looks like brake fluid leaking on my back tire ? I see no master cylinder? Please point me in the direction to learn more of this system .20240511_191807.thumb.jpg.e00d75e4628e2106b55adf7fa524141f.jpg20240513_184319.thumb.jpg.9f4cf8b52380385f2b998ba20169eac7.jpg20240511_191737.thumb.jpg.0044efa7f5c4bba2392cb5f221ce5f9b.jpg

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The fluid is likely from a bad wheel seal.  The air brakes are easy to adjust, as long as its not rusted realy bad. How familiar are you with the wheel end parts of air brakes?

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1 hour ago, Joey Mack said:

The fluid is likely from a bad wheel seal.  The air brakes are easy to adjust, as long as its not rusted realy bad. How familiar are you with the wheel end parts of air brakes?

I know nothing . Was hoping for a guide to some literature and pictures.  It only did that when I left e brake on . Drove it three times since and no new fluid has shown . What's the proper name for the valve on my firewall in first picture

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Whoa boy



Hang on a moment before just chucking a bucket full of coin at this

Some really basic fault finding 

With full air pressure, put your foot hard on the brake pedal AND HOLD IT THERE

Once the air gauge changes with the air use of air, does the pressure slowly drop or does it stay constant 

If it doesn't drop slowly you dont have any major leaks and the brake chambers don't need changing 

Looks like these are S cam brakes

With no brake application NO FOOT ON THE BRAKE PEDALPEDAL You should be able to just pull the slack adjusters by hand

The slack adjuster should pull out the rod to the can (brake chamber), when let go it should spring back in quickly, almost with a snapping action

If these don't, the S cams or the rollers on the shoes are binding and the assembly will need disassembling, cleaning, lubricating and replacement of worn bushes etc

This is simple work and cost virtually nothing but time and as a bonus you get to learn about things

Some other quick advice for what its worth 

Pull the wheel and hubs and brake drums as a complete unit

A pallet jack comes in handy for this

If you don't have a pallet jack

A board greased up is next most common thing 

Either way pulling the hub and wheels as one is the simpleset and easiest way



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based on reading original post and studying the pictures , I strongly advise finding a mechanic to do the job and be their assistant. brakes pulling could be simple out of adjustment. oil on shoes, bad can etc . looking at picture I see a combo brake/ trolly /stop light switch not only having wires off but a drain valve for a plug. unless of course it's there to drain excessive air !!!what the f==. lower air line has a low air sender disconnected   and there's more .

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My Fleetstar's of that vintage have S cam rear and wedge front.  With it pulling badly on brake application, it could be an S cam out of adjustment by a lot, or it could be a frozen wedge, which happens more often.

 That isn't a low air switch in the lower line, it is a hyd brake light switch! 

 I know it is new and you want to drive it, but please have someone who knows a bit about trucks come by and give you a hand. You get stopped on the road, and the result is likely a tow bill and a ticket.

A single rear with no spring brakes and a 2 speed axle (or had one at one time)? So must have a driveshaft E brake? 

 I worked on a school bus that was set up that way (air brakes but only driveshaft E brake), but that would be fairly rare.  Most air braked trucks are required to have spring brakes, I thought the school bus was an exception (didn't want a school bus stuck on RR tracks because of an air problem).

 Early stuff, yeah they had air brakes and either drum or disk driveshaft brakes.

I know most had to have spring brakes starting back in the 50's or 60's. 

You listed your location as USA, which isn't helpful, if you were near me, I'd drop by and at least get you started on what needs to be done. As it stands I have no idea what part of the country you are in.

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