[Richard]

Just a little more background on the test fixture based on my own air leak fix journey. I think it is easy to change the solenoid valves as the first attempt at fixing issues with the coach settling over time. Over a period of years and thinking about it I realized two problems with that thought process. One, we don't have a good way of knowing the solenoid valve is leaking, and second those puppies are expensive to just throw money at the problem. I made some fixtures to test the valve off of the coach but that requires removal.

So the idea for the isolation fixture was born. The isolation valve acts as the solenoid valve since it is just downstream of the six pack. If the side leaks down with the isolation valve closed then the leak is between the six pack and the air bags. If it stays up then the leak is in the six pack solenoids. The fixture should cost less than twenty bucks to make and that is 20 percent of the cost of one solenoid valve.

Here is where it gets interesting for Tom. If the coach stays up with the isolation valve closed then how to tell which of the three solenoids is leaking? The down solenoid is easy. There is an exhaust hole on the back of the six pack. A little bit of soapy water on that hole will tell if it is leaking. You can put the isolation fixture on the air line coming from the HCV valve next. If that stops the coach from sagging then the travel solenoid is leaking. If that doesn't stop the sag then the only valve left is the UP valve.

Sorry for the heavy duty logic but I have had two long drives in two weeks and windshield time makes me think.

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One more thing. Having a fixture on board would allow you to air up the coach and travel if a HCV valve failed on the road