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Topic: Front Air Leak (Read 719 times) previous topic - next topic

Front Air Leak

This is a real strange occurrence.  Crawl under coach and air leak is above the front tank I can feel it but not tell what is there as I cannot see.  The strange part is that the aux compressor comes on at will.  Pulled fuse still runs and turned switch off I installed and it still runs.  Only way to get it off is to start big engine.  When I go to travel mode the front the coach raises too high in the front.  Can drive but not correct.  No leak when in leveling mode.  Leveling is not possible but makes an effort.  Any ideas.  Calling Nac on Monday for an appointment.  Can drive there with front end high.  Tks Dan
Dan & Shirley Stansel
2002 U295 4020 AGDS Build#6054
Towing Buick Enclave & M &  G Braking
Emerald Bay, Lake Palestine, Texas
MC# 16650

Re: Front Air Leak

Reply #1 –
Dan,

This is INDEED a strange combination of problems - I'm scratching my head trying to figure what would account for all of them...

I am totally mystified by the Aux compressor that runs without any visible source of 12 volt power.  :o

You might try the "Emergency Leveling Procedure" (link below) and see if it will let you level your coach for the trip to NAC.  You are basically disabling the "Travel Mode" and must level the coach manually.  Once you have it level, it should hold that setting while driving.

Emergency Leveling Valve Override Procedure
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Front Air Leak

Reply #2 –
Dan, check the adjustment for the front ride height valve. A couple of times, the adjustment on mine has slipped when the front of the coach was lifted high. I could observe the change based on the dirt/corrosion patterns on the linkage. Also, debris or damage in the ride height valve might cause the symptoms you describe. Use safety jacks if you put human parts under the coach.

I have no suggestions to offer regarding the 12VDC compressor. Some power is getting to it from somewhere.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Front Air Leak

Reply #3 –
OK Tks for the help.  I did discover that if I hit the stop switch all goes off and the aux compressor goes off as well.  When I put it into travel mode the front end raises about 10 inches above the front tires.  I have it lowered back down now But using the leveling sysyem to do that and when it goes back into travel mode the front raises again.  I am going to try to get into Nac next week and see what is causing this problem. Can not put the front slide out as coach must be level for it to come back in without so major popping sounds.  Will post as to the cause of this occurrence when I know the answer.  FOT or MOT for its issue?????
Dan & Shirley Stansel
2002 U295 4020 AGDS Build#6054
Towing Buick Enclave & M &  G Braking
Emerald Bay, Lake Palestine, Texas
MC# 16650

Re: Front Air Leak

Reply #4 –
Quote from: J. D. Stevens –
Dan, check the adjustment for the front ride height valve.

^^^^^ What Dave said ^^^^

In Travel mode the ride height valve controls the air to the air bags.  If you're exceeding desired ride height in travel mode, the ride height valve(s - 1 for front axle, 2 for rear) aren't working or set correctly.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Front Air Leak

Reply #5 –
Tks everyone.  Got to be the issue however; I can not make the repair as I can not see above the tank where the leak is located. Should MOT or FOT which would be best???😕
Dan & Shirley Stansel
2002 U295 4020 AGDS Build#6054
Towing Buick Enclave & M &  G Braking
Emerald Bay, Lake Palestine, Texas
MC# 16650

Re: Front Air Leak

Reply #6 –
Dan, check the linkage to the front ride height valve. Also, use some "percussive maintenance" on it. (Tap the ride height valve with a rubber hammer.) On our coach the ride height valve is visible and accessible. I expect it would be in a similar location on your coach.

Locating a leak by where the sound is coming from can be tricky. I had a significant leak at the hydraulic accumulator (near the engine) and there was a loud sound of air escaping near the air tanks at the front of the coach. The air was not escaping, but flowing rapidly through the air lines to the rear of the coach where the real leak was located. I fixed that leak with "percussive maintenance" on two occasions. It has worked properly for years since those "adjustments."

You might consider calling a mobile service technician. The ride height valves are used on big trucks and trailers. A good technician should be able to at least get your coach back "on the level" while in travel mode. He (she?) might be able to fix the air leak in case it is an issue separate from the high front end.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Front Air Leak

Reply #7 –
Quote from: Dan  Stansel –
Should MOT or FOT which would be best???😕

Any of the Nac shops that deal with leveling/air bags should be able to handle this.  FOT, MOT, Bernd, Isaac at Old Town Motorcoach, or Beau Reece.  Choose your preferred shop/shop rate.  Isaac and Beau are both mobile in the event you prefer not to move the coach.  Contact info for those guys should be on the forum, let me know if you can't find it and I'll get it to you.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Front Air Leak

Reply #8 –
Tks J D and Michelle: I will try to get it to Nacogdoches, after all I drove from Forrest City, Ark this way about 389 miles. Dan
Dan & Shirley Stansel
2002 U295 4020 AGDS Build#6054
Towing Buick Enclave & M &  G Braking
Emerald Bay, Lake Palestine, Texas
MC# 16650

Re: Front Air Leak

Reply #9 –
Got appointment for MOT for Wed.  They had a cancellation.  Will post what I find out and we will see who is correct.  Dan
Dan & Shirley Stansel
2002 U295 4020 AGDS Build#6054
Towing Buick Enclave & M &  G Braking
Emerald Bay, Lake Palestine, Texas
MC# 16650

Re: Front Air Leak

Reply #10 –
Today just got back from MOT. Great service as usual.  Problem air leak was Ride Height Control Valve.  Also had air dryer replaced.  Now ready to go again.  Dan
Dan & Shirley Stansel
2002 U295 4020 AGDS Build#6054
Towing Buick Enclave & M &  G Braking
Emerald Bay, Lake Palestine, Texas
MC# 16650

Re: Front Air Leak

Reply #11 –
One thing I learned from Keith was that the aux compressor has two power sources. One from the hwh system.  Also the dumb thing I thought was: the holes top and bottom were drain holes in the big slide.  Turns out that is where the pins lock in.  Keith sprayed some Corrison X silicone spray top and bottom and this helps with the locking and controls any squeaking.  Really helped for a smooth in and out.  If they get dry in the 02 model squeaking could occur when driving as they have nylon bushings.  Dan
Dan & Shirley Stansel
2002 U295 4020 AGDS Build#6054
Towing Buick Enclave & M &  G Braking
Emerald Bay, Lake Palestine, Texas
MC# 16650
 

Re: Front Air Leak

Reply #12 –
Your power supply comes from a 40 amp breaker in your storage compartment and is fed by wire # 18 . They have small reset buttons on the side .
Rob Barb & Pyper
2002  U320  40'
2010 Suzuki Grand Vitara