[Reagan]

Mikee. Apples and oranges. Follow me closely on this.

An air bag failure of the size shown will lose accessory air fast. If you switch level low into manual mode ASAP it effectively stops all air from flowing into the burst air bag. It will even allow air to build back into the accessory air system.

But if you do not stop the air flow, air will leak down in the brake systems until it hits the protection valve pressure, at which point the brake systems will be protected and fully functional. The conpressor will run trying to fill the accessory side, but as long as it continues to work your coach will be safe to drive if you ignore the impact of something that has caused loss of accessory air.

That is the end of my comments relative to an air bag or other accessory system catastrophic failure.

Now let’s talk about the application of emergenacy brakes. If you lose air pressure to either the secondary or primary air systems you retain brakes on the remaining system. Your emergency brake does not deploy. If you lose air pressure at the emergency brake, such as a broken hose or failed diaphragm both primary and secondary lose air pressure trying to keep pressure onto the emergency brake to keep it released. If the leak is big enough both lose air until the emergency brake deploys. If you want to nurse the coach along, apply the parking brake, that allows both brake systems to re-pressurize, and release the parking brake until you lose presure again, but during that time you can roll a ways. How far you roll depends on the size of the leak and how long it takes to re-deploy the emergency brake.

At that point your best option is to cage the brake and/or plug the hose that leaks. By caging the brake you lose some emergency brake power, but you can retain full service brakes, and plugging the hose you have eliminated the problem until you can do the correct repairs.

Neither issue is related. But having said that it all depends on how well a coach has been maintained and checked. If you as an owner do not drain your tanks in sequence and verify the operation of the protection and check valves you may in fact lose brake system pressure if there is an accessory system air leak. The only way to know you do have functioning check and protection valves is to do a system check either yourself or instruct a technician to do it every time there is access to the underside of the coach.

[Archived]

Jon is not saying you will lose brake air if you blow a air bag , if all the protection valves are working and the check valves , let’s stop this Jon knows and has helped hundreds of people , you can not learn all there is to know by reading the damm manual. Period !!!! You need experience only one way to get wisdom

First. Bad judgement then you get experience then you get good judgement then wisdom . Jon has done that , he has wisdom on the coaches

If everybody understands what the systems have to help us it’s easier , there is a SR1 valve with a shuttle cock inside that works on pressure and it will send air to the system with the most air if you have a brake failure hose or relay valve in front it will send air to the back brakes you may have two maybe three applications left to stop the coach , there is more to it than a damm check valve or pressure protection valve , must I go on ????? Just for those that are interested if the park brake valve leaks it will drain out the primary and secondary tanks together. There also is a R14 relay valve with a balancing port on the top of which is hooked to the park brake so you can not blow up the brake can if its on and you push the foot pedal down at the same time the park brake is on , Just some helpful information if you need to know!!!!!!!!!