Air Leak

[Jerry Emert]

The attached pic shows an air leak I found on the last trip.  The coach stays up on the air bags for days but the air in the tanks depletes in a few minutes after I shut down the Cat.  My question, how is the fitting constructed?  My concern is that the fitting, where my finger nail is pointing is part of the tank instead of part of the airline.  If I start turning at that point will I twist it off and have to replace the tank?  I see that there are threads, are they on the air line or the tank?  Is there a fitting of some kind between the line and the tank?  Do I just unscrew it and put Teflon tape on it and torque it down?  Or...should I just suck it up and hire a real Mechanic?
Thanks in advance.
Jerry

[Lee Welbanks]

Jerry

Where is it leaking air? That looks like a threaded reducing bushing threaded into the tank. Take a wire brush and clean off the area so you can really see what you have. I don't think it would be the weld on the fitting in the tank, the threaded portion in the tank is called a weld o let and I have never seen one leak but it could be possible, probably one of the threaded fittings. Just drain all the air off and take them apart and put some thread dope or teflon tape and put it back together. I have also seen fitting crack, rare but it does happen.

[Jerry Emert]

Ok that could have gone better.  I think the fitting that was actually threaded into the tank was cracked causing the leak.  I cleaned the area of the leak with a small wire brush.  I took the airline off with no problem.  I put the wrench on the (nut) coming out of the air tank.  As soon as I put a small amount of torque on the nut it deformed into an oval shape and snapped off.  At this point you are thinking that I put a bunch of torque on it or turned it the wrong way but believe me when I say it was very little pressure on the wrench.  When I examined the nut it had an obvious crack all the way through it in the exact place it was leaking from.  I can tell that because it was very clean and shiny because I just cleaned it with the wire brush.  So whats next, do I need a new tank or just a professional?

[Edward Buker]

Jerry,

To clarify, the problem is that a portion of the fitting is still inside the threaded portion of the tank when the fitting broke? Also we assume that it was a brass fitting?

On page T12 of this plumbing tool catalog is a T handle reamer, I have read some have had luck with that tool with a broken nipple. Tapping it in end unscrewing. On page T15 there are several nipple extracting tools. I would consider talking with a "seasoned" good plumber on the technique.

http://www.generaltools.com/assets/images/catalogs/Catalog_Plumbing.pdf

Later Ed

[Lee Welbanks]

Been there don that, the internal pipe extactors work pretty good, hopefully they put some pipe dope on the fitting when they put it in. Being brass it won't be rusted up.
I have a set of expanding old school Proto internal pipe extractors that I have used.

[Jerry Emert]

I figured there would be a way to get it out.  Just wasn't sure how.  Thank you.   I'm concerned about stuff falling inside the tank and not being able to clean it out.  Is the air filtered somewhere sufficient enough so that debris won't screw up the system?

[Lee Welbanks]

Is this fitting hole on the side or bottom of the tank? One way I've done before is when you get the threads cleaned out fire up the motor and hold your gloved hand over the hole until it builds up some pressure and then let it go. It will blow all the crap out the hole, do it a couple of times.

[Jerry Emert]

Is this fitting hole on the side or bottom of the tank? One way I've done before is when you get the threads cleaned out fire up the motor and hold your gloved hand over the hole until it builds up some pressure and then let it go. It will blow all the crap out the hole, do it a couple of times.

Thanks Lee, great idea!  The connection is on top of the tank, of course.  Looking from the front all connections are at about 1-2 o'clock on the tank.

I'm still trying to wrap my head around how easy that fitting popped off.  Is it possible that all the treads came out with it?  Could they be that shallow?  Again, I'm not a very experienced mechanic, almost zero experience in the last 30 years or so.  I think I remember seeing threads in the hole.  Could I have been that lucky?  I guess I'll have to go over to the MH again today and take a look.  I'll update later.  Thanks again to all.
Jerry

[Lee Welbanks]

Hey it just broke happens all the time. You still have probably threads left in the hole that have to come out one way or another.  Might be easier to remove the tank so you can get at it or take it to someone who can do the job. I would remove it do it right and reinstall.