[encantotom]

ok, i have rebuilt two sets of these mac valves (with clarke) and i am trying to remember how they are set up and dont. i just copied the way they were hooked up previously. good news, at least a few years ago these were readily available valves and cheap compared to the newer hwh ones.

now back to your questions..

though i cant totally tell from the plumbing, i believe you are right that the top two are the left and right rear travel valves.

you only mentioned that with the key on, that they skinner valves would be activated. if they are some kind of pre-valve for some reason, they would need to be on. i dont quite understand the way the air is flowing from the regulator i admit.

what you didnt mention is if the mac valves are energized with the key on and in travel mode. i suspect they are.

if you turn the key off, and the airbags hold steady, then the air circuit for the airbags is working. if you have the key on, and the switch in leveling mode (which turns off the travel mode and travel solenoids) does the coach air up?
if the engine is on and running, and in travel mode, do the airbags inflate to ride height?

there are two things that i think of. since you have been playing with the ignition switch and that if i remember right controls the leveling panel (all toggle switches like my 90 was) i am wondering about that circuit. if you can turn travel mode on and off using the switch and the coach goes to travel height and or stays where it is when in level mode. then i suspect it is not related to the switch.

the second is the simplest of all. if the coach works in all modes, but is just venting the rear (front is at ride height in travel ok) in travel mode, i would check to see if some how the ride height valves on the rear have gotten knocked out of adjustment. if they think the coach is too high, they will be venting air as they should to lower to ride height. and the valves would be venting. do they vent all the way flat or just low?

anyway, a few things to think about. clarke has more experience with his and hopefully he will weigh in

i found the leveling/rideheight setup using the mac valves to be very very responsive compared to the hwh setup. almost like a low rider car adjustment

tom