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Topic: Moisture in rear "Dry" tank (Read 308 times) previous topic - next topic

Moisture in rear "Dry" tank

Passenger front airbag wouldn't inflate in drive mode. Started searching for leaks.  Have 2 questions.
1) My rear dry tank had lots of water/ condensation in it. Thought maybe check valve was bad and letting air from aux compressor enter tank. The coach has had leveling on for couple months while my wife has been staying in it. No moisture evident in any other tanks. My understanding is aux compressor doesn't supply air to brake tanks. Put reman air dryer on 10 months ago. Where is moisture coming from?
2) Figured Ride height valve must be bad, no other apparent major leaks. Ordered Haldex pn#90555105 from Napa. Can get 2 days for $175. Bit more than other places but quicker turn. Thought I'd get ahead of game and remove old unit. I sheared adjustment rod trying to remove bottom nut. Called Foretravel parts thinking just get whole deal and expedite shipping keep Napa one for spare. NOT!! Foretravel has Merritor $300 for valve only. Another $200 for the rod assembly. NFW. Anyone know correct part number for Haldex rod assembly for 01 U320?
2001 4010 U320
Build 5875

Re: Moisture in rear "Dry" tank

Reply #1 –
The only way you are getting wet air in the wet tank is from the engine compressor. The dryer should be taking the water out before it gets to your wet tank.  Since you replaced the Dryer and I am guessing the descant filter, my guess it you have a big air leak somewhere and the compressor is having to run a lot and they dryer can't keep up, heater circuit for the dryer is not working, and/or descant is expired.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Moisture in rear "Dry" tank

Reply #2 –
One of these number kits should have all the parts together in the box. Haldex KN27000 Meritor R3013222 if you hunt around you can find a knock off for about $30 but for name brand expect a little more at about $100.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Moisture in rear "Dry" tank

Reply #3 –
Quote from: turbojack –
The only way you are getting wet air in the wet tank is from the engine compressor. The dryer should be taking the water out before it gets to your wet tank.  Since you replaced the Dryer and I am guessing the descant filter, my guess it you have a big air leak somewhere and the compressor is having to run a lot and they dryer can't keep up, heater circuit for the dryer is not working, and/or descant is expired.
That's what I would think but if that's the case I would think moisture would be present in all tanks. Only show moisture in rear tank.
2001 4010 U320
Build 5875

Re: Moisture in rear "Dry" tank

Reply #4 –
Quote from: Spiderhitch –
That's what I would think but if that's the case I would think moisture would be present in all tanks. Only show moisture in rear tank.


Keep on driving without doing anything,  it will then start showing up in the other tanks and valves. 

You caught it before you started seeing water in the other tanks.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Moisture in rear "Dry" tank

Reply #5 –
How often do you drain the tank. Could the water have been there before you replaced the dryer? When I was buying my coach prior owner never drained the tanks. Probably had ten years of water in the aux compressor tank. Gallons. Got some out of the other tanks but much less.

Re: Moisture in rear "Dry" tank

Reply #6 –
Quote from: dsd –
How often do you drain the tank. Could the water have been there before you replaced the dryer? When I was buying my coach prior owner never drained the tanks. Probably had ten years of water in the aux compressor tank. Gallons. Got some out of the other tanks but much less.
Guess it could have. Haven't drained for couple years since last worked chasing leaks. Do drain and check wet tank. It's always been dry. Guess I was surprised wet tank, aux tank and front brake tanks were all dry. Only water was in rear brake tank. Will keep close eye on it. May rig up drains that are more accessible in wheel wells like wet tank drain.
2001 4010 U320
Build 5875