Good day gurus. I can hear air leaking from behind the rear wheels. Using my leak detector, I tracked it down to the bottom side of the manifold that holds the air dryer filter behind the left rear tag tire. The leak is coming from where the hex head is located in the attached picture. The picture is the bottom of the manifold to which the air dryer filter is located on top. My question is whether I can try tightening the hex bolt or if that is not recommended? If I do tighten it, how hard can I crank down on it?
I went ahead and tried tightening it. It feels like there is a nut on the other side that is turning with the bolt up inside the manifold. Therefore it is not getting any tighter. It is still leaking at a pretty good rate and loud enough my old ears can hear it without aid of my leak detector. I can hear the system compensating for the leak by pulling air from the tank above the tag axles about every 15-20 seconds. It doesn't take long to deplete the air in the tanks. Any ideas are welcome.
Not sure what we are looking at and not familiar enough with the new Newells to say that that is. Looks like it might be part of the purge valve? A picture a little further out that shows what the device is we are looking at might be helpful.
I attached two more photos. One from the side and one more from the front quarter looking down. It is difficult to get a much better shot because the tag tire and side wall of the coach get in the way and I did not have it blocked up for me to get under to get any better picture. The first picture in this thread is the underside of the unit.
(11-21-2025, 06:24 PM)Superannuated Peregrinator Wrote: I attached two more photos. One from the side and one more from the front quarter looking down. It is difficult to get a much better shot because the tag tire and side wall of the coach get in the way and I did not have it blocked up for me to get under to get any better picture. The first picture in this thread is the underside of the unit.
That appears to be a Bendix AD-IS air dryer, what is leaking is the purge valve. Its held in with a big circlip. You should be able to pull the whole purge valve out, probably should just get a new purge valve kit and put it in. You can just try cleaning and lubing the o-rings.
When was the last time the air dryer was serviced?
I put red lines on the circlip that holds the purge valve in:
Thanks, Jeff. Dryer was last serviced in late April of this year. It was not leaking a couple of weeks ago when I was on a 3-day trip. Where can I get a kit? It's leaking bad enough that I may try taking it out and lubing it as you suggested while trying to get a replacement kit. Of course it's not easy to get to. Will take a bit of uncomfortable contortioning around drive train components (when isn't that the case). I see the clip you are describing. I'll see if my brother has a pair of clip pliers, otherwise I'm going to purchase some. Will make the process much easier with the right tool.
(11-21-2025, 07:22 PM)Superannuated Peregrinator Wrote: Thanks, Jeff. Dryer was last serviced in late April of this year. It was not leaking a couple of weeks ago when I was on a 3-day trip. Where can I get a kit? It's leaking bad enough that I may try taking it out and lubing it as you suggested while trying to get a replacement kit. Of course it's not easy to get to. Will take a bit of uncomfortable contortioning around drive train components (when isn't that the case). I see the clip you are describing. I'll see if my brother has a pair of clip pliers, otherwise I'm going to purchase some. Will make the process much easier with the right tool.
I kinda figured it was serviced, as it appears someone did not put back the nozzle that goes on the purge valve. That is the 4 holes you see where it looks like screws should go into them. Looks like Jim below has posted all the part numbers and the information on the dryer you should need. Jim is one of those gurus that has a newer coach like yours, he needs to be your new best friend!
