Problem With Air Leveling

[rwitt]

I have a 2008 Monaco Camelot with air leveling only. We purchased it about 1 1/2 years ago and I started have problems with what I presume is an air leak. In looking for that I found a aux air pump with small air tank in the front of the coach. One of the wires was disconnected. When I connected it the pump started but it was extremely loud inside the coach and ran frequently. I finally disconnected the wire so it wouldn't run. I've continued to have problems with low air and have been starting my coach to build it back up.

I just learned (thank you Brett) that I shouldn't be starting the engine and letting it run without driving it to build up all of the pressures. Also, that that the aux air should be used when parked. I connected the wire back on the pump this afternoon and it was still loud. It waited for a while and then started coming on about every 20 mins. Then about an hour ago, it started and wouldn't go off. The air tank blew off twice but the pump kept running. I went out the pull the wire and it was too hot to touch. I got a pair of pillars and disconnected the wire.

I don't know if the pump is bad or the sensor. The control panel has Valid Inc on it, but the pump and tank both have power gear. I have been trying to find the pump and the sensor on the web with no luck. The pump is Power Gear P/N 501184 s/n 0706055580/ The air tank is Power Gear P/N 501263 S/N 0704030508. The sensor shows ON 90 PSI OFF 120 PSI 20A and an # 3096 on it.

Has anyone has this problem and does anyone know where I can find these parts?

Any help will be greatly appreciated. We are in the TX Valley in McAllen, TX and I have not been able to find anyone who will work on the air system as yet. If anyone out there is in this area or familiar with this area and knows who I can call, please let me know.

[wolfe10]

Ron,

What air tank "blew off"?

Was this an over-pressure valve? Air dryer? Other?

[kaypsmith]

If the pump still comes on and produces air, it is probably OK, the pressure control valve needs to be replaced. Here is an ebay page with many listed http://www.ebay.com/sch/i.html?_odkw=air+compressor+pressure+switch&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.X12+volt+air+compressor+pressure+switch.TRS0&_nkw=12+volt+air+compressor+pressure+switch&_sacat=0

Almost any mechanic can replace it if you don't want to tackle the job.

[rwitt]

Brett,

I was in the coach so I'm not sure which tank. It was up front where the pump and aux tank are. There is a relief valve on top of that tank. I used a lot of soapy water and check the relief valve and all the connectors for air lines and didn't get any bubbles. The Gage's showed 115 psi for both tanks. However, this morning they were at 85 psi. I checked the oil stick and in the filler area. No rust on stick and no white gunk in the filler. Does that mean I'm probably OK reference moisture in the crankcase?

Kaypsmith,

I looked at the link you provided. I didn't see one with a 20A listing. Most of the 90/120 12v switches that mentioned amps were 3.5A

I appreciate the help from both. Any other ideas?

[wolfe10]

Glad you don't show signs of moisture in the crankcase. Still a good idea when the weather is nice and dry to take it out for a long drive to rid the crankcase of moisture.

No problem with a low amp switch. Just means you will use a RELAY to power the pump. That is far better for both the pump and the switch anyway. Extra cost for relay and extra wiring about $12. Let us know if you need wiring instructions-- is is easy.

[kaypsmith]

I prefer the relay, but here is a link for 12/24 volt up to 20 amp.

http://www.quadratec.com/products/92043_0017.htm?sgsc=C6Z06ZR1C6Z06ZR1&utm_medium=compshop&utm_source=googlemerchant&gclid=CMniwP7X_sgCFQiNaQodhpUK8w

If changed over to relay will normally last much longer.

Brett I was probably typing while you were earlier.

The pressure switch itself may be the where the actual leak is, it is only a rubber diaphram that holds air in and pushes the actual switch.

[rwitt]

Thanks to both of you. I connected the wire this morning and the pump came on and ran about 20 sec and turned off. I am assuming that the pressure control valve is 12V. I think I will try the lower amp and the relay. What relay do I need and where can I get it? Please send me the wiring diagram. Is the 3.5A OK to use if I put in the relay?

When it was running this morning there were small bubbles coming from the terminal that I had the wire connected to so you are right kaypsmith. Although it was very slight and it quit when the pump went off. I released some air in the tank and connected the wire back. Pump came on and ran about 10 sec and the bubbles started again while it was running. I think ther must be another leak(s) somewhere causing the pressure in the two main tanks to fall every day???

Again, you're help is greatly appreciated.

Ron

[wolfe10]

Ron,

I would get a relay at least 50% larger (handle more amps) than the pump requires. It is the FUSE, not a relay that protects the wires. An oversized relay will just last longer. Any auto parts house will have them. Should find them under $10.

There are 4 terminals on the relays and they come with wiring instructions, but here is how they work:

You will use the old wire that went from the pressure switch to the pump on the relay's positive signal terminal. Negative signal terminal to any chassis ground.

A new positive wire from large-gauge wire from house battery (probably already have one in the compartment with the pump, or you could even tie into the present wire on the "IN" side of the pressure switch) to positive IN on the relay. Then new wire large-gauge wire from relay to pump.

When the pressure switch closes, it signals the relay to close and power goes from that large gauge wire, through the relay and directly to the pump. No heavy power running through the pressure switch with it's probably voltage drop.

So a relay, some large-gauge wire (sized for small voltage drop given amp draw of pump-- let us know amp draw and how long the wire will be from positive source to relay and relay to pump) and a relay.

BTW, this also works very well to brighten headlights and any other circuit that runs a lot of amps through a switch. That way the switch is not doing the "heavy lifting", it is only signaling a relay that is designed for heavy lifting to pass current to the device.

[tbutler]

Ron,

I am puzzled by the link between the main air tank/braking system and the leveling system. We have a Monaco with air leveling only and the two systems are independent when the coach is parked and in auto level mode. Yes, you can run the engine to raise air pressure on the leveling system but the leveling system shouldn't lose pressure to the braking system when it is operating properly. If that is the problem then there may be a leak from the leveling system back into the braking side of the operation. Air pressure on the braking side will drop while the pressure on the leveling system is maintained by the auxiliary pump . When the system is put in travel mode, and only then, the main coach pressure maintains the air bag system.

Our auxiliary pump is located near the front axle where the auxiliary pressure tank is located. Our pump makes a noticeable noise but isn't what I would describe as loud. The sensor/controller for the leveling system in our coach is located in the basement compartment, on the ceiling under the refrigerator. Our system is HWH instead of Power Gear so there may be some differences in components but it sounds as if the basics of the system should be similar. I have never heard our auxiliary pump activate the relief valve. Our leveling system operates at 110 PSI.

When we went to Alaska, the mounting for the auxiliary air pump broke and I had to improvise repairs. Our pump was mounted with springs used to reduce vibration noise. The springs weren't up to the rough roads and gave out. I replaced the springs with rubber bushings and those have worked fine since 2006. If the mounting springs for the pump are shot, the pump will make more noise.

Undoubtedly, if there is an air leak, that would cause the pump to run frequently so finding the leak anywhere in the system, supply lines, air bags, etc. would be a priority. We have found that there are times when the leveling is difficult that will cause the pump to run more frequently. The system is designed to keep the coach level and it will adjust the coach when the level is changed by shifting load by using water from fresh water tank and running it into the grey water tank for example. Temperature will also cause a full airbag to swell or shrink more than a mostly empty air bag and this will cause the coach to go out of level and will initiate operation of the pump to raise a low point on the coach. The size of the auxiliary pressure tank is not sufficient to prevent the occasional operation of the auxiliary pump. The automatic system will also adjust level by dumping air from a high point in the system which causes a loss of pressure. When it comes to leveling the coach, the auxiliary pump will operate for longer periods of time when it is necessary to raise the rear of the coach since that is the heaviest part of the coach. The auxiliary pump is designed for intermittent operation so if it operates for long periods of time I would not be surprised to find it very hot. Our operation manual recommends dumping all air from the leveling system before initiating the automatic system. This lowers the coach and also minimizes the amount of air in the air bags which minimizes the changes in level due to temperature change.

We are in Edinburg and when I need work on the coach I have taken it to Burt Ogden RV (956-585-4444) in Mission. I don't think they do on site service but they may be able to recommend someone who does. There are lots of mobile services in the RGV but I've never used any so can't make a recommendation there. Feel free to message me if I can be of further assistance.