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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: busshawg on June 01, 2010, 02:18:42 PM

Title: tag air pressue
Post by: busshawg on June 01, 2010, 02:18:42 PM
Can someone tell me if the 2 valves inside the passenger side engine access door control the air pressure to the tags, or are simply used for dumping each tag air bag individually. Thinking bypassing these valves.
Thanks
Title: Re: tag air pressue
Post by: James77MCI8 on June 01, 2010, 02:48:21 PM
They  control dumping the pressure to the bags on the tag axle. Handy if you have a flat on the tag, you can chain that side up. Also handy for putting more weight on the drive axle if you need it for traction. I wouldn't get rid of the valves. MTW
Title: Re: tag air pressue
Post by: JackConrad on June 01, 2010, 03:29:14 PM
Leave those valves.  Those valve saved me once when we had to drive through a mud hole. Ie dumped the air from our tags to put weight on the drive axle. Barely made it through and probably would not have made it if I had not dumped the air.  Jack
Title: Re: tag air pressue
Post by: busshawg on June 01, 2010, 03:35:58 PM
I also have a dump vavle on the dash that should still work for dumping both sides, or does the dash valve dump through those 2 as well. I understand it would be benificial in the case that I want to chain one up.
Title: Re: tag air pressue
Post by: mikelutestanski on June 01, 2010, 04:19:16 PM
Hello;    If you have a factory installed dump valve switch on the dash it only dumps the pressure to about 12 psi.  The valves on the back dump the pressure to 0 psi...  The rear valves are to be used when chaining the wheel up I believe..
    FWIW    regards and happy busssin    mike
Title: Re: tag air pressue
Post by: busshawg on June 01, 2010, 07:24:42 PM
Thanks once again guys, all the info I need in short order. I have decided to bypass only while I rebuild my valves.
Title: Re: tag air pressue
Post by: buswarrior on June 03, 2010, 12:34:51 PM
You need to be able to take the air off the tags to pick the coach up.

The only thing preventing over-extension of the tag suspension, and resulting damage and the risk to those around of being struck or crushed by the parts when they let go, is the shock absorber, which should not be called upon to do this.

The proper method for the MC7/8/9/A is to chain up the tag before lifting the coach.

You need to keep a method for letting the air out of the tag suspension for these safety procedures.

happy coaching!
buswarrior