Jim,

Good advice above. Recognize a few things so you can speak somewhat authoritatively with the "mechanics".

The air in your suspension system is "locked" in place by the corresponding 5 port Norgren valve when the ignition key is off. If you bus leans left or right or sags down in the front your search efforts on your coach are limited to the respective air bags, the fittings, the 5 port Norgren, and in the case of the rear, the 3 port Norgren between the tag and drive axles. Included in the search for possible leaks is the corresponding three port valve which serves as the exhaust point when dumping air during leveling. PERIOD.

Because you have a 2000 coach and a Liberty you have three three port Norgrens in the steer compartment that are part of the system. You also have an accumulator air tank at their respective axle positions, apparently to serve as addidtional air volume for the air bags. Their drain fitting must be leak free.

Here is some additional leak finding comments besides the ones listed above. If the 5 port valve is leaking internaly no amount of soapy solution will find the leak. Soapy solution is only of value in finding air bag, air fitting, and air drain valve leaks. Internal leaks on Norgrens require a bench test or the use of a stethoscope or ultrasonic leak detector. If the mechanics don't understand that you are paying them for nothing.

If you suspect the 5 port Norgren for example there are other ways to verify it leaks. Remove the incoming air lines and plug the ports. If it is leaking back through the valves the bus will not drop because the path is blocked with the plug. A Norgren valve can leak "sideways" past the spool and let air escape from the end caps. That is visible with soapy solution, but only if you can see bubbles. Just like trying to see bubbles due to leaks around or under the bottom can on the air bag there are some spots you will not be able to see leaks.

But let's get real.....a full set of valves for your Liberty is less than $1000 if all are bought brand new from Prevost. A full set of air bags for your bus is $1100. Allow 10 hours for all air bags to be replaced (Eric has changed one himself in less than 1/2 hour, Joe, Roger, Brian and I have all agreed an hour per air bag on average is a safe number.) Allow 1/2 hour to 3/4 hour per Norgren (you have about 10) and you are done. Spending money to have someone look for soap bubbles, especially if they are not experts is a waste. Get Joe C. to deal with it. He knows what it takes to get the job done.