Skip to main content

Topic: Can't build air, not the D2 governor (Read 1596 times) previous topic - next topic

0 Members and 1 Guest are viewing this topic.
Can't build air, not the D2 governor
I could use some forum wisdom here... I was coming down the mountain from Idyllwild and got the air loe air pressure alarm. After pulling over and checking things over, I used the aux compressor to raise the coach (which adds air to the front and...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #1
The D2 governor does two things.  It signals the air dyer to purge and it lifts the valves in the air compressor to stop the pumping action.  If the valves won't return to service, you won't have air.  Think stuck.

Re: Can't build air, not the D2 governor
Reply #2
I'm thinking along the same direction as Old Toolmaker.

There's really only 3 components involved in the air pressure "generation" process:  the engine air compressor, the D2, and the air dryer.  Since your malfunction is intermittent (randomly...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #3
Bypassing the air dryer (my next step as well as hopefully aiding my move down to storage) should tell me if the compressor is doing its thing or not... likely a stuck valve in the air compressor if it doesn't. I did spray a bit of WD40 in the...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #4
As it is right now, the aux is only triggered by the leveling system. I have yet to wire in the switch to control it directly. It will work to get me down to storage if I raise it up as high as I can and then let it settle to ride height.
Don
 


Guests must Login or Register to view full posts.

  • dsd
  • [*][*][*][*][*]
Re: Can't build air, not the D2 governor
Reply #5
Don I'm unfamiliar with our air compressors but on other compressors reed valves are used. I have seen them have one of the mount screws back out and rotate so as not to seal. Also seen them fatigue crack. I'm very curious to your findings. I'm...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #6
I have had the unloader valves stick on my crane. It uses a Bendix compressor. I was able to spray Corrosion X into the head assy. by removing 2 bolts and fixing the problem. The valves on it are like an automobile engine and the valve stems were...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #7
R&R of the air compressor is not something I look forward to...

Don,

If the dryer checks out OK then here are some thoughts on the compressor and D2.

If the compressor pumped any at all that...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #8
Can't help with fixing the problem but could you use your generator and an air compressor plugged into the external connection to keep it aired up to move it?

Re: Can't build air, not the D2 governor
Reply #9
Can't help with fixing the problem but could you use your generator and an air compressor plugged into the external connection to keep it aired up to move it?
An electric compressor will not...

Guests must Login or Register to view full posts.

  • oldguy
  • [*][*][*][*][*]
Re: Can't build air, not the D2 governor
Reply #10
The generator will be able to drive a big enough air compressor to do the job.

  • Dub
  • [*][*][*][*][*]
Re: Can't build air, not the D2 governor
Reply #11
I was slammed with sticker shock when I looked for an air compressor for my 8.3.. If I had been home I would have tackled rebuilding my on in my shop. Your lucky your home Don and not in El Paso Tx.

Re: Can't build air, not the D2 governor
Reply #12
Don I'm unfamiliar with our air compressors but on other compressors reed valves are used.
Scott

Scott sit back and think for a moment.  The compressor is gear driven and turns anytime the engine...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #13
Thanks for the thoughts Mike... Our coach has a Holset compressor (which is bthe reason it has to have the external isolation valve on the air dryer). I see that find it parts may have a rebuilt unloader assy for about $75. I will have to remove...

Guests must Login or Register to view full posts.

  • Texhub
  • [*][*][*][*]
Re: Can't build air, not the D2 governor
Reply #14
Vet10 latest finditparts discount i have. May expire at 1158 pm today.
Mark

Re: Can't build air, not the D2 governor
Reply #15
Not sure whether or not these are direct replacements for the Holset model I have, but a search on "Holset QE296EC
" yields 3558072X by HALDEX - Remanufactured Cummins/Holset Style Compressor - QE296
Note that it lists just the QE296 without the...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #16
Found one that has similar "assembly number" (plus the "X")  to the metal tag in your photo:

Cummins/Holset Compressor - 3558186X/QE296

If you look at the different QE296 compressors in the link below, you can see 3 different mounting flange...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #17
Not sure whether or not these are direct replacements for the Holset model I have, but a search on "Holset QE296EC
" yields 3558072X by HALDEX - Remanufactured Cummins/Holset Style Compressor...


Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #18
Thanks for the research Chuck!  ^.^d I want to get a rebuilt unloader assy but the one that is suggested at Find It Parts is shown as not available. This part looks like it should be used across many models. I wonder how universal they are... I would...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #19
If I can find a rebuilt to buy, I plan to take the old one apart and maybe fix, so I would just eat the core charge.
Don
That would be my approach as well. 

Richard

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #20
Update and some head scratching :o I got the coach down to our boondocking location safely. The head scratching is because bypassing the air dryer did not result in the compressor doing its thing. So... I add air with my trusty HF ultra quite...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #21
Don,

Here is the part numbers that should fit the QE296 unloader. PAI # 220038 or Cummins 3803766. Make sure that you don't get a kit for the SS models as they won't work on the QE compressor.  Here is a video of what you are up against. ...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #22
Pamela & Mike, that is an excellent video! Another video that makes it clear what type of air dryer Is applicable to the QE compressors used mostly before the 2000 model year, apparently only on the ISC powered model coaches.
...

Guests must Login or Register to view full posts.

Re: Can't build air, not the D2 governor
Reply #23
Don,

What a lot of people don't understand is the need to use the correct air dryer that is mated to the compressor you have.  Very good explanation in that video.

Mike

Re: Can't build air, not the D2 governor
Reply #24
I have a new PURest air dryer that says it isn't compatible with Holset compressors. Without the isolation valve, I don't think the OEM "Pure Air Plus" is either. My thinking that the addition of an isolation valve See picture below)  would do...

Guests must Login or Register to view full posts.