Community Forums

zfuntime · 06-27-2016, 11:53 AM

We have a 2007 Tiffin phaeton that is losing almost all of the air in the air system in roughly a 24 hour period. We have had a freightliner repair service in GA and a RV dealer in FL work on it. Freightliner in GA found a small leak at a fill valve, and they changed it. There was still a leak. We took it back to them. They couldn’t find anything else. The dealer in FL found some more valve leaks and a leak on an airbag. They changed a rear airbag, tightened the valves, and repaired small fitting leaks. We are still having the same problem. The air system does fill back up when the coach is running, and stays filled as long as the coach is running. Any suggestions?

jacwjames · 06-27-2016, 11:59 AM

Do you have 2 tanks, does your air gauge have 2 indicators. If so are both of them leaking down??

A leak this bad should be able to hear it. Start the engine, get air to pressure and go from wheel to wheel and listen. If you can't hear anything go to engine compartment and listen then to the front of the coach.

I assume you have air ride which does have leveling valves, one of these may be stuck but it shouldn't let the whole system bleed down. There are check valves in the system to prevent reverse flow. If you have 2 air tanks they should be isolated and not let air go from one to the other tank. One of these check valves may have a piece of debris in it letting the air slowly leak out back towards the compressor.

Best way to find a leak is to take a spray bottle and spray each connection starting at the compressor, to the air dryer, then to the tanks then follow all the lines to the braking system

zfuntime · 06-27-2016, 12:53 PM

Jim, We do have two indicators (gauges), and they are both leaking down equally, as they always have. I cannot hear any air leak at any location with the engine running, or the engine off, and neither of the repair people were able to hear any leaks either. The coach has been checked end to end by both service people, and the leaks they located and fixed were located using a spray bottle. Yes, we do have air ride. I will discuss your suggestion about the leveling valves with the service tech. Thank you so much for your reply.

Gary RVRoamer · 06-27-2016, 04:45 PM

Take the coach to Freightliner Factory Service in Gafney, SC, and they will have you squared away in a day. And you will be in & out of the shop on the appointed day. They keep their appointments!

TQ60 · 06-27-2016, 06:08 PM

Do you have air or hydrolic leveling?

If air good luck but if hydrolic get jacks deployed and ready.

Run engine to get up on ride and wait until compressor cycles off.

Shut down engine then manually raise each corner just enough to feel it move or maybe up 1 inch if you have a spotter.

This will get leveling valves far into lower position which shuts off raise side more.

We had one that when level the lower side wss just touching and caused compressor to cycle at a 1 minute rate.

Simple adjustment cured that.

rkainsworth · 06-27-2016, 07:19 PM

We had a leak in the O ring at the air dyer, started slow hard to find then let go...lost all air, e-brake kicked in and then the leak was finally located.

Rich

Hal3848 · 06-27-2016, 09:32 PM

Like the other gentleman said take it to Gaffney SC I just got out of school there for Camp One Had mine there two leaks also works like a charm and mine was a new coach Also Mike that is a head of the school would be happy to help you give him a call. Good luck

zfuntime · 06-28-2016, 03:45 PM

Thank you everyone for your replies. We have talked to a tech at Gaffney, and are considering going there. It is 700 miles from us and their first appt. is late August. So, that is kind of a problem. We have been there for service many times, and have always been very happy with them.

jelag · 06-28-2016, 05:40 PM

So I've owned several trucks with air brakes... we would always do an annual inspection with nothing more than dish soap and a 1 gallon sprayer... we'd spray and inspect.. and repair... all the parts are available in the aftermarket... including air valves and other parts.. we'd also look for air lines that were rubbing and insulate them with some heater hose that was split and maybe a nylon tie or two...

make your you spray all around the air chambers when you do this... do not attempt to repair them... they are a replacement item only....

its what I'd do to save a 700 mile one way trip....

Ray,IN · 06-28-2016, 08:35 PM

Quote:

Originally Posted by jelag

So I've owned several trucks with air brakes... we would always do an annual inspection with nothing more than dish soap and a 1 gallon sprayer... we'd spray and inspect.. and repair... all the parts are available in the aftermarket... including air valves and other parts.. we'd also look for air lines that were rubbing and insulate them with some heater hose that was split and maybe a nylon tie or two...

make your you spray all around the air chambers when you do this... do not attempt to repair them... they are a replacement item only....

its what I'd do to save a 700 mile one way trip....

I did that once, found the leak. The only caveat to this is; run your MH up on ramps high enough that if your coach suddenly loses all air pressure while you're underneath you'll still have breathing room so you can crawl out.

jelag · 06-28-2016, 09:14 PM

Of course Ray is right... in the case of a truck you have no problem... the Freightliner Chassis I've been working on has hydraulic jacks... but I still use jack stands as a safety...

Virtually all the parts in the air system is the same as whats on the same size truck in the same class... spring brakes (air cans), air valves, leveling valves, air lines, switches and interfaces are used but almost all the truck companies so an owner can get service anywhere...

Ray,IN · 06-29-2016, 07:06 PM

I don't know about freightliner, but Spartan chassis will not build up air pressure with jacks down. Thus the ramps suggestion.

gacamp · 06-30-2016, 05:02 AM

Quote:

Originally Posted by Ray,IN

I don't know about freightliner, but Spartan chassis will not build up air pressure with jacks down. Thus the ramps suggestion.

My Spartan MM chassis will build up full air pressure while jacks are down, in fact thats how I was advised to raise the coach, let full pressure build than hit retract.