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dreamchasers
05-13-2009, 11:02 PM
Several POG members were aware that I have taken on the project of replacing all the AC hoses on my dash AC system (R-12). I have been plagued by leaks. After each repair and recharge, the system would operate as designed for several months, then another leak. Every leak occurred at the point where the rubber hose is connected to the re-usable fitting supplied by Prevost on the hoses. Prevost has previously issued upgrade instructions for this series of AC hose.

I attempted to have Prevost, Fort Worth replace all these hoses when I was in their shop in late 2007. They gave me an estimate of $6,000 to replace all the hoses! Well, I thought take was ridiculous.

All of the hoses can be purchased from Prevost for approximately $850. The hoses come fully assembled with new fittings on all hoses. I purchased bulk AC hoses in the sizes I needed for approximately $350. A savings of $5,650 was realized by doing this work myself.

With a PIB (Pain In the Butt) factor of 7 (0-10), the job took some focus. A younger guy would probably give it a much lower PIB factor, but for an old guy like me, too much bending and reaching....

I replaced the hose with Airquip FC802 series. This hose is a barrier hose, so upgrading to R-134a is easily possible. Plus, the FC802 series hose fits the reusable fittings used on the existing hose. This project is doable, but if anyone tackles this, be sure and 'use plenty of lubrication' (That should be easy for most of use to remember). After cleaning the reusable hose fittings, apply R12 refrigeration oil on the hose and fitting before assembly. Trust me, this is a very important part of the assembly.

My Country Coach has a Wabasto unit mounted in the cabinet, drivers side, behind the rear wheel. Over the years, the heat produced by this device weakened the rubber hoses. Most of the leaking hoses were in this area.




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These hoses are the suction and discharge hose set that connect to the compressor and bay area behind the left rear wheel. Dirty and brittle from years of 'crud' and engine heat.

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This a one of the bypass hoses. Note the oil saturated end of the hose. This guy had been leaking a long time.

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Another AC hose with evidence of long term leaking.

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Picture of old hoses on left and a couple of newly assembled hoses on the right.

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This is a cross section of the hose I used. Note the polybromide polymer barrier in the center of the hose.

The project is doable, but does take some time and patience.

Hector

BrianE
05-13-2009, 11:12 PM
Good job Hector and a great start for a new article. Would a sketch and/or description of the exact location of the hoses be possible? I know there is a hard pipe run from rear to front with the flexibles here and there in between. The here and there is the scary :eek: part. Many thanks.

dreamchasers
05-13-2009, 11:19 PM
Good job Hector and a great start for a new article. Would a sketch and/or description of the exact location of the hoses be possible? I know there is a hard pipe run from rear to front with the flexibles here and there in between. The here and there is the scary :eek: part. Many thanks.

Brian, An article can easily be made.

In your comment 'hard pipe run from rear to front with the flexibles here and there in between'. On my coach, metal pipes do run from the front to the rear, but I did not see any flexible hoses between the front and rear of the coach. I remember reading this on the forum before, however the Prevost drawings of these hose/piping runs do not indicate any internal rubber hoses.

I hope I did not miss any?

Hector

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truk4u
05-14-2009, 12:12 AM
Great job Hector... Prevost told me there were in fact flex hoses mid coach and that was the reason they had just charged a guy 9000.00 for all hoses and conversion to 134. Another knowledgeable company told me there were no mid hoses, copper from front to back.

Sure would be nice to know if there are mid hoses or not.:confused:

lonesome george
05-14-2009, 11:48 AM
Good one Hector!
Sooner or later we will all face A/C hose leaks, when my time comes I'm going to follow your path, do them all.
In preparation I have started watching Richard Simmons DVD's and joined Jenny Craig.