We were in Nac for the Ladies Driving School in early Nov. On the way there, the aux air compressor started cycling more than usual. While at FOT we had them trouble shoot the air fittings and replace as needed. Cost us ~ $400 for this. Two months later we are experiencing the same issue. I walked around the rig listening for leaks and heard none. While the aux air compressor was running I unplugged the the unit and could hear a leak. Got out the windex and started spraying air fittings around the pump. I located the source (see picture). Tried to tighten the nut, but could not tighten enough to stop the leak entirely. Question: What is the "shiny part" the hose is connected to? Is it a check valve? in-line filter? something else? I looked at the manual schematic and could not determine what the item is.
From proximity of pump - likely a one way check valve, so air can flow only in one direction.
Leak is likely in fitting/ferrule, not the check valve itself, but the connection on the end. Should be a relatively simple fix, others will chime in with best way - but I would break the connection, let any residual pressure bleed off and then take off the line and inspect/repair/replace as necessary. Likely local Napa can help you with any parts needed.
Check valve. Fitting is a push in type, you can cut tubing, and install new fitting.
Try this before you replace the fitting.
Where the leak is, push in (toward fitting) with the black tube, then simultaneously push the grey ring in (toward the fitting) while you pull out on the black tube. They make a special tool for this, but you can use a open-end wrench that just fits over the tube as a substitute. With the ring pushed in, the tube should pull out of the fitting. Carefully cut about 1/2 inch off the end of the black tube with a new single edge razor, or use the special cutoff tool. The end of the black tube should be cut perfectly straight across, with no burrs or deformation. Put a little spit on the end of the black tube, and push it straight back into the fitting. Trying airing up coach and see if the leak is fixed. If it still leaks, you'll need a fresh fitting.
Malida Pipe Tube Hose Cutter Scissors1/4" 3/8" 1/2" PVC Nylon PU for Water... (https://www.amazon.com/Malida-Scissors1-filters-Reverse-Osmosis/dp/B0168X4QBQ/ref=cm_cr_arp_d_product_top?ie=UTF8)
PneumaticPlus TC Nylon PVC PU Plastic Tube & Hose Cutter Cut Up To 3/4" OD... (https://www.amazon.com/PneumaticPlus-TC-Plastic-Cutter-Tubing/dp/B00BU9K07S/ref=sr_1_12_sspa?s=hi&ie=UTF8&qid=1546550724&sr=1-12-spons&keywords=parker+plastic+tube+cutter&psc=1)
Parker Hannifin PTC-001 Plastic Tube Cutter: Industrial Tube Fittings:... (https://www.amazon.com/Parker-Hannifin-PTC-001-Plastic-Cutter/dp/B077PTQRRW/ref=sr_1_1?s=hi&ie=UTF8&qid=1546550724&sr=1-1&keywords=parker+plastic+tube+cutter)
Note: the black composite fittings and the brass fittings work exactly the same:
https://www.youtube.com/watch?v=BBo0TYdk65g&list=PLFB89tlgd0Np6o9b_S92tQGvzEXfxDNx5&index=3&t=0s&frags=pl%2Cwn
I've found it best to replace the push-on fitting with a compression ferrule fitting wherever possible.
Push-on fittings will cause problems after years of service. But yes a quick fix to try is to cut the end off and try to insert the new end into the push-on fitting.
Thanks to all for your help. Wondering if I could just replace the short piece of plastic hose with copper tubing and appropriate fittings? I prefer flare fittings to compression.
There are a lot of quick connect fittings on your coach, so why just change one to a flare fitting? The fitting may be fine and even if it has failed it lasted 16 years and has a simple fix.
I personally wouldn't go to the trouble making/using flare fittings as it's not a high pressure hydraulic system.
X2. Properly installed push-on fittings work great, and nylon tubing is commonly used for pressurized air lines in many different industries.
No need to reinvent the wheel.
Reference the picture in my original post: What Is This? I found out the item is a 1-way check valve with the air traveling away from the leak in the fitting at the bottom of the valve. I also discovered air leaking out the solenoid valve at the bottom of the glass bowl when the aux compressor was off. I then thought air was leaking backwards from the 1-way check valve. So I replaced the 1-way check valve, but it didn't help. Still have the same problem. It is so bad I cannot use the aux pump because it is cycling every 20 minutes and gets too hot. After a period of time the air system in the coach leaks down to zero. What really makes me angry about this problem is I had the air system checked out at FOT in early Nov. Background: Last April I had all the air springs replaced except the tags at Redlands Truck & RV. Everything worked fine and life was good. Took a 3000 mile trip and no issues, then on our way to Nac. for the Ladies driving school, the aux air pump started cycling every 80 minutes when it had been cycling about twice a day. So when we were at FOT I had them check out the air system, replace any defective valves and replace the tag air springs. Left Nac. after the LDS and drove ~ 200 miles to Lewisville TX. Started having problems and it has gotten progressively worse. Now the air system is really jacked.
David,
When the compressor is off that solenoid valve looses it's voltage and opens so it will drain any moisture during the run cycle of the compressor. The air should stop after a second or 2, not flow all the time. So you still have air leaking backwards through a check valve.
I don't have an HWH air diagram for an '03 right here to look at so I can't be for sure if you have another check valve that is your problem or the one you installed is bad. Even new some times check valves come from the factory not right. I would venture that you have a second check valve that needs looking at. Seems like there should be one hid somewhere close to the safety valve that I see in the pic. FYI the safety valve is the brass valve sticking up with a pull ring through the stem. We have a check valve in that location so give it a look.
Mike
If you are a motorcade member call James T and he will send you air diagram for your coach if you would like one.
Air can be vexing, but it is straight forward to work on. How far are your from NAC. I have not had consistent good luck dealing with air issues on shops outside of NAC. MOT has usually been relatively fast at finding and fixing the leaks for the lowest cost. But you can fix leaks one day and have more a few days down the road.
Keep us informed
Tim Fiedler
Gen-Pro.biz
630 240-9139
"But you can fix leaks one day and have more a few days down the road. "
Same goes for Vacuum leaks, only harder to find !
David,
Just have had time to pull the air prints for your coach. You should have another in line check valve at the discharge side of the air dryer (the thing with the glass bowl) According to the prints it is a closed nipple check valve that is threaded directly into the filter discharge, the other side of the check valve will have a "T". The "T" will have a pressure switch on one side and the other will go to the suspension piping. The safety valve showes to be mounted on the inlet side so look on the other side for the check valve.
Hope this is clearer than mud.
Pamela & Mike
Here is an air system for the 2003 U320 with a tag. I have a detail for the compressor but I can't find it. I will keep looking.
Make sure this drawing is applicable to your coach. There is a box with the starting build number in it in the title block. This one starts at build number 5920.
A great big thank you to all for your concern and help. We are "camped" at Nellis AFB in N. Las Vegas NV and have been since the end of Nov. We had hoped to travel to the Foretravel gathering in Quartzsite the middle of this month, but that's iffy right now.. Since arriving at our current location it has been a 3-ring circus trying to keep our "land yacht" afloat. Problem 1 - the HWH auto leveling is our of adjustment. I tried to adjust it myself but have not been successful. Problem 2 - air leak near the aux compressor, thus the requirement to level with blocks. Problem 3 - washer leaking water, flooded the coach and ruined the water pump. Problem 4 - entry steps will not retract completely. Problem 5 - intermittent coolant leak when I start the engine. Problem 5 - toilet intermittently will not flush. Problem 6 - the park water supply system will be shut off for repairs for 5 days beginning today at 6pm. Thanks for listening.
David,
This sounds like 6 good reasons to bail out and go to Q. There will be others there that should be able to help you get some of these things patched up.
Mike
I have a used water pump that is good if you need it.. Im in Las Vegas.. let me know
Thanks for the offer of a replacement water pump. Ordered a new one from Amazon immediately when the other one failed. Couldn't afford to delay since the park will lose water service for 5 days. Water will be shut off in ~ 5 min. New water pump arrived on time and I managed to install it. Just had one leak. Plumbing is my least favorite trade. I can't recall a plumbing job that did not leak after repair or installation.
If you manually level the coach and then turn the system off does the coach stay level? If it does then forget about auto level. I always had to manually level the coach because auto level will not level the same every time and I wanted my doors to stay where they did not open further or close on their own.
I can manually level the coach, but with the air leak, the coach only stays level for about 10 minutes. We found the auto level when it worked, not all that accurate. I'm kind of OCD about level, wanting the toilet room and shower doors to stay put, not just swing where ever. I don't like walking around feeling like I am drunk. I was thinking I could fabricate some screw jacks out of 3/4 to 1 inch #8 bolts. I would manually level the coach using the air springs. Then I would insert the bolts length wise near the bags between the coach frames so when the air springs lose air the coach frame would settle on the bolts. Would want to run this up the flagpole with FT engineering before proceeding.
Let me recap the air leak problem. After we arrived in Las Vegas I noticed the aux pump was running more than normal. When the pump cycled off I could hear air slowly leaking so sprayed some windex on fittings around the pump. Discovered air leaking from the fitting to the input port of the common 1-way check valve. Later I found air leaking from the water trap solenoid after the pump cycled off. I figured the common 1-way check valve was worn out since it was probably as old as the coach. Ordered a new check valve from NAPA ($40) and installed it. Didn't fix the problem. So I sent a number of pictures to James T at FOT and learned from him that there is an HWH 1-way check valve in the manifold assembly. The HWH owner's manual shows the HWH 1-way check valve in another location, specifically between the water trap and the desiccant bowl. James explained that by locating the check valve after the .5 micron filter it provided relief of pressure on the aux pump when the water trap solenoid opened when the pump cycled off. This makes it easier for the pump to start on the next cycle. I ordered a new HWH 1-way check valve ($35 + shipping) from HWH since it was about $15 cheaper than FOT. It is currently in transit. Installation doesn't look easy. Will update my post when item arrives and I get it installed. Hope this solves the problem.
First picture, middle arrow. See post #3 for guidance on fixing the leak in the fitting. Don't know about the other leak you show.
Rich
From your list #3 seems the most serious. Sorry to hear that happened to you.
Did the washer itself leak, or was it a PEX connector? When you say "flooded the coach", to what extent?
I will start a new topic on the washer to explain the "flood".
David, did you ever fix the problem with the HWH 1 way check valve at the manifold on photo #3? If so, was the install difficult and do you have the part number? I now have the same problem. Once the aux compressor turns off, it's leaking out of the solenoid valve at the bottom of the bowl. Thanks in advance.
Robert
Not sure of the size or male/female configuration, but;
Control Devices Brass Ball Check Valve, 1/4" NPT Male, New, Free Shipping... (https://www.ebay.com/itm/Control-Devices-Brass-Ball-Check-Valve-1-4-NPT-Male-New-Free-Shipping-/361273091203?_trksid=p2047675.m43663.l44720&nordt=true&rt=nc&orig_cvip=true)
Thanks!