Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 14, 2025 ...

We have the same question - the newer FTs (last year or so) we've seen do not have the desiccant bowl.

We and others have found cracking in the bowls of the system that allowed moisture in.  Our desiccant bowl was also quite corroded inside and we replaced it (both bowls, actually) in 2011 Photo upload - HWH aux compressor filter bowl replacement .  Based on that single data point (   ) the timing is about right for your 2004.

This discussion prompts a further question.  The air pressure guages on the dash show an increase in pressure when the engine is running thanks to the engine driven compressor - and - they go up when the 12v compressor is running.  Without questioning that there might a difference, I had assumed that the air tanks are all connected and both compressors are independently doing the same thing.  Is this correct?

Michelle, how do you remove the stone filter from the first in line dryer?  I see a pliers in the picture but I'm not sure what to turn.

Leaving the switch off should keep the 2 lines isolated.  HOWEVER - if you see the A and B tanks go up with the switch off and only the 12V compressor running, there's a good possibility the solenoid valve is leaking through.  Ours did and we replaced it in 2011.

Michelle

There should be a switch on the panel by the driver's left arm that says "Air Tank".  Flipping it on opens a NC solenoid valve that links the lines so the 12V compressor can help build pressure (so you can start airing up without running the big engine - being considerate of your campground neighbors). 

Leaving the switch off should keep the 2 lines isolated. 

I took at look at the Air Schematic (drawing B-2026 dated 3/24/03) to figure out what connects to what.  Much if not all of this is discussed in other posts but I wanted to put it all together.

The 12v compressor has 3 outputs: the wet tank, the slide out seal tank and via connections on the output of the right and left brake tanks, the air suspension.  I couldn't find the "Air Tank" switch and valve in the diagram as Michelle describes it but without the switch on, the 12v compressor feeds the slide out seal tank only as a normal occurrence. 

However there isn't any gauge to tell you when this tank is full and the seals are properly inflated.  You have to just trust that the compressor is working and keeping the slide seals inflated.  I understand now why some folks have to disconnect the fuse or the compressor connection manually to keep if from running.

Barry, did you keep the desiccant filter active? 

Mine is leaking around the o-ring and won't build pressure.  The screen above the dessicant is really corroded and should be replaced.  I put the bowl and the pink desiccant in a zip lock in the pickup and after being out in the Oklahoma sun there is a lot of moisture in the bag.  That moisture would have been in the system without the desiccant. 

I've not gone in search for parts.  Didn't see anything on the Grainger site like this filter.  Do I need to order parts from Nach or is someone likely to have it in Oklahoma City?

I'd like to get it back together without waiting on parts.

Thanks

I replaced mine from Grainger WILKERSON Dryer, Desiccant - Desiccant Dryers - 5Z610|X06-02-000 - Grainger

Barry,

How about a little info on why you chose that particular size dryer?  I was looking at a much larger one such as this:

http://www.nationaltoolwarehouse.com/15-SFCM-In-Line-Desiccant-Dryer-1-Quart-P138705.aspx

Am I missing some important detail that would make a larger one not work.
Thanks