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Discussion Starter #1
I've had a few people ask for information re: maitenance of the air-brake system. The manual says many things that you need to know unfortunately alot of people and previous owners do not take the time to do the basic checks/cleaning to ensure proper braking/system operational liveability. Thus many owners get frustrated and pull the whole thing out. I have 2 manuals...one on operation and a parts explosion of the air/assist braking system. From the Brake Booster, Tire Inflation Cylinder which does have a filter inside and does come apart unknown by many and the Pressure Regulator, Antifreeze pump, Compressed air tank, Trailer Brake Valve and finally Air Compressor. Many of you have this on your truck. Some know what they have and some do not. So let's start out with the basic maitenance of the air brake assist system. Feel free to opt in if something doesn't seem right. I will try to only quote from the manual...Be advised all 404's are not the same especially in this field. Plumbing could be different/airlines/placement ect.


Reconditioning of Tire Inflation Cylinder.

Well here's the good news....Yes there is a Filter in the Tire inflation Cylinder. I have actual exploded pictures and yes it does show that this part does come apart at the cylinder housing. ....To recondition it says to....1: Unscrew water and oil separator hose connections at bottom and remove bottom valve with spring....(Secured by a punch mark.)

2: Unscrew housing cover at bottom. Remove sealing ring, spring and filter.

3: Unscrew connecting piece at top after removing wing nut. Pressure spring, valve, plunger ect. are exposed. Clean all parts thorougly - rubber parts in spirit of alcohol only - and grease slide surfaces with acid free grease. Replace damaged parts.

4: For reassembly proceed vice versa....

Now for the Pressure Regulator....

Removal

1: Make system pressureless.
2: Unscrew lines ( of tire inflation cylcinder and antifreeze pump).
3: Unscrew pressure regulator from console.
4: For reinstallation proceed vice versa


Reconditioning of Pressure Regulator
1: Unscrew cap of overpressure bottom valve
2: Pull out valve set.
3: Continue disassembly, if required, by re-moving the safety disc. Replace rubber rings, if required, also rubber sealing disc bottom.
4: Unscrew lateral closing screw with filter sealing ring to check for free flow.
5: Unscrew closing nut of adjustable pressure control valve above. Remove spring with retainer as well as valve plate.
6: Unscrew adjacent closing screw for over-flow valve with filter sealing ring. Remove cone spring and sealing plate.
7: Clean housing passage completely. For cleaining of rubber parts, use only spirit of alcohol. Grease sliding surfaces slightly with acid-free minderal oil. Replace damaged seals and reassemble vice versa. Test for leaks. Adjust pressure on top threaded cap secured by counternut. Use 8mm hexagon socket for making adjustments.

:D
 

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Discussion Starter #3
Actually the above is from the Workshop Manual. The one you are referring too is the Instruction Manual. Both are a good source of info to take care of the Assist air brake system.
 
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