By-Pass Aux Compressor

August 12, 2015, 06:11:16 pm

These comments may not be adaptable to all coach years and models and you should decide for yourself if it is workable and a safe way to operate, especially if you were to elect to get under a coach to work with the air tanks.

I recently had the auxiliary compressor quit on a one slide 2001 and was left with the prospect of slide bladder deflating and coach unleveling along with the serious question of how I could get back on the road. Local rains were also a factor if the slide were to be closed but I was unable to inflate the bladder (some tapes can do much to help seal the opening in that event).

I called Mike Rodgers at MOT and he had a solution to a temporary fix to get us home. After we talked, I began to think of two other ways to accomplish this. Be aware, I have not tried either but feel confident it would work.

1. From Mike R., I could splice into a nearby air line and, using a T-connector, insert the aux line that was to deliver pressurized air to my third front air tank. You will need a 3/8 inch compression T for that if your system is like mine. You may need help to identify which line to splice and which line to move from you aux compressor to the T. In essence your coach compressor will thus supply pressure to the the third tank that is used for park leveling and slide bladder control. There are some limitations to this in that your coach compressor will need to run to fill the tank so if you are not moving you may need to crank at times.

2. I got to thinking about this and decided you might be able to connect my tire filling compressor I carry to the aux air out line and use that second compressor on a temporary basis to fill the third tank. Mike R. agreed. I had found that all I needed, I think, is the compressor I carry and a fitting for the 1/4 inch air hose via that it can match up to the 3/8 inch compression fitting that connects the aux air line to the compressor. I felt I might set the compressor to about 80 psi, air it up and then disconnect compressor or leave it attached for subsequent running. You may want/need a valve in line to close the compressor line when you turn it off. I do not know if an existing check valve would prevent the pressurized tank from bleeding back thru the aux compressor line you use.

Mike Rodger said sounded good, simple. Then he suggested I go to the drain valve of the third tank, put air in that way, using a rubber tip blow tube connected to my spare compressor I use for tires.

3. However, I realized that I may have a different and easier way to do that for our coach. I have the drain valve on the bottom of the third tank connected to a valve on a bracket just inside the fender and in front of the driver front tire. I could use that route rather than getting under the coach. So I got a rubber tipped air blower ($10) and found that it would just fit into the opening of the drain valve mounted on the bracket and not have to get under the coach. Thus all that I need is to attach the spare compressor to the blow tube, insert the tube into the valve opening, run some air in and turn of the valve when done.

I imagine that tank could handle 120 psi but I do not know so I figured limit the pressure I put in to 80 psi.

Conclusion: I have not tested either method yet but I am carrying the necessary connections. The aux compressor is behaving quite strangely, having blown two fuses and taking much too long to air up the tank. We suspect that after 150,000 miles, it may need to be replaced.

If questions, perhaps I or other members can provide more information. Note, if you are not aware, the tank aux system is needed to deflate the slide bladder and bring the slide in for travel so rain in thru a deflated bladder opening is not the only issue.

Mike

Re: By-Pass Aux Compressor

Reply #1 – August 13, 2015, 12:26:46 pm

Thanks Mike, good subject, & good info. Now, how do you identify which valve goes to which tank?

Re: By-Pass Aux Compressor

Reply #2 – August 13, 2015, 06:02:49 pm

Mike
Believe we have the same model. In mine there was a check valve, I believe in line 57, right after the aux compressor. I had this changed to a quarter turn valve I normally leave open. This lets the engine main compressor inflate the slide bladder and create the vacuum to deflate the bladder. We only need the aux compressor to maintain level when parked with engine off.

Re: By-Pass Aux Compressor

Reply #3 – August 13, 2015, 10:03:55 pm

Mike, I too have thought about I would handle a failure of the 12 volt compressor. My solution was to install a Schrader valve in Line 75, which goes to the Slide air tank. My compressor shuts off at close to 120 psi and I already had an air pressure gauge in place. BTW, I don't think there is a check valve in Line 75.
Now, if necessary, I can use any tire pump to pressurize that tank. Full disclosure; I haven't tested this yet either.

Dick

Re: By-Pass Aux Compressor

Reply #4 – August 13, 2015, 10:17:04 pm

Meant to include a photo.

Re: By-Pass Aux Compressor

Reply #5 – August 13, 2015, 10:22:08 pm

Dave, i imagine you do not mean how did i identify which valve went to each tank, but if you did, i confess i tried to trace the lines from the fender to the three front tanks. That seemed to work ok but to verify i opened first one valve and then another, watching pressure drop on the two dash gauges.

The third valve opened with no dash change was my third tank.

I very appreciate each of your thinking on this. I think Dick and, or Mike P has better options than i but I need to think about each, see which I will install. Dave, i will reread your question and try to get my thinking in line with what you need to know.

Thanks...i believe others will find this thread of value...either that they have not really had to think about this or one of the means suggested may give them a refernce vua the Forum search that they might get back on the road.

Mike

Re: By-Pass Aux Compressor

Reply #6 – August 14, 2015, 12:22:08 am

Thanks Mike, you answered my question fine. Thanks again !

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