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TDInewguy's avatar
TDInewguy
Explorer
May 04, 2013

Rig Down! No air pressure... Help please

Hello all,

I just picked my 2002 Itasca Horizon 39QD from Winnebago -- they did paint & body work to the coach over the last two weeks...

So I drove it about an hour south to Henderson, IA and met with a church (for what I do for work - sound/video/lighting systems)

Once I fired up the rig to head home, which is a 3 hour drive, I got about 3 miles from the church and the "Low Air" light and buzzer came on. I had about 65psi in both front and rear tanks.

I have tried everything I know to do and i cannot build any more pressure. Started and stopped the motor, revved it, purged the air tanks, I even tried sending compressed air into the schrader valve inlet on the air dryer. (the air dryer is only about a year old or less)

There is no apparent hissing or leak anywhere that I can tell, but it more seems like the compressor is unloaded and just not building any air pressure.

Help! i''m stuck here and my kids are home without me! (I'm a young widower with two young kids - 5 and 7) I had a babysitter today, but she had to leave, so I was able to get someone else to stay the night with them, but I need to get this thing running and home safely!
Class A

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  • Big_Katuna's avatar
    Big_Katuna
    Explorer II
    May 04, 2013
    Hope that is it.. Please keep us posted. Not fun being stuck. I had a ride height valve that was stubborn on cold mornings. Discovered that blowing hot air from a hair dryer would make it work.
  • TDInewguy's avatar
    TDInewguy
    Explorer
    May 04, 2013
    I am so happy! There is a local diesel repair shop that had a governer on the shelf!

    (I'm stuck in a Godfathers pizza parking lot, and they even delivered it!)

    So I'm in the midst of replacing it right now -- so I will know shortly if that was the problem.
  • John_S_'s avatar
    John_S_
    Explorer II
    May 04, 2013
    You can remove the black cover from the air governor and turn the screw fully to compress it and then open it back up. You might be able to get air pressure that way as the diapphram is probably stuck. You should replace it if that is it at the first chance. Make sure you get one with an earlier startup, some start at 75 other at 95. We need air in our rigs for suspension so we use the higher turn on pressure. I am not sure what winnie uses but this is the best 25 bucks you can spend for a spare part. Oh and bleed all the air out before you change it.
  • Ivylog's avatar
    Ivylog
    Explorer III
    May 04, 2013
    OP, since you still have 40-50 psi in the system, the two valves under the large bolts on the air compressor are good/not leaking and do not take them out with air in the system.
  • Ivylog's avatar
    Ivylog
    Explorer III
    May 04, 2013
    Tapping on the governor will not hurt, but it's function is to put 120psi air to the unloading valve in the compressor to stop building air. The unloading valve is like a normally closed switch so the pump should put out air without a working governor.
    Assuming no air leaks, broken hoses, or air coming out of the air dryer I would start by taking the hose off from the inlet to the air compressor and put your hand on the inlet and see if you have suction... not pulsating air or no indication. If no indication of air movement then I'd remove the two large bolts on the top of the heads and see if something is holding one of these oneway valves open. If you have pulsating air, then remove the two bolts that hold the air intake elbow off and see if there is any movement of the unloading valve with the engine running. Hopefully there is something holding this valve open. If no suction or pulsating air, then the drive for the pump is broken. This may help in understanding this system.
  • TDInewguy's avatar
    TDInewguy
    Explorer
    May 04, 2013
    It is a CAT 3126 engine on a Freightliner XC Chassis.

    I don't hear any loud hissing sound.

    I did try to push air into the system via a small air compressor into a schrader valve on the air dryer, which dumped a bit of water when I pushed the center pin on it... but I have about 40-50 psi in my tanks now, but pushing air into the bottom of the air dryer will just amont to it going nowhere (helpful) that is.

    So if it is the governer - is that something I can tap with a hammer to try and free up or is it a replace only deal?
  • tony_lee's avatar
    tony_lee
    Explorer
    May 04, 2013
    Stuck open unloader valve on the air dryer normally makes a lot of hissing noise but a stuck governor on the compressor will be quiet.

    Heard of people getting out of trouble by tapping/banging the governor to free it.
  • indyzmike's avatar
    indyzmike
    Explorer
    May 04, 2013
    The manual for a Jet system says that you can air it up through the Schrader valve with the system in manual mode. That is supposed to hold the air in the bags.
  • Executive45's avatar
    Executive45
    Explorer III
    May 04, 2013
    First of all let us know what engine you have in your Winnie...my first guess would be a stuck unloader valve. Look on your air dryer for one and tap it with a screw driver or wrench. My second guess would be a bad governor. Any mobile mechanic can fix the in about 30 mins or less if he has one on his truck...good luck....Dennis

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