Older Monaco Windsor - flexible air intake hose replacement - where to get it

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Mar 12, 2013
My 1997 Monaco Windsor  with C8.3 275-HP Cummins has a 7" diameter flex hose that goes from the roof air intake stack into the air filter.  Mine was breaking down and had holes in it.  Monaco didn't have it or know where to get it.  (Note: later Monacos have a stainless steel pipe instead of flex hose).

It is called "RFH hose" and is used in wierd HVAC and industrial applications.  WW Grainger has 25 feet of it for $500.  Ouch!  After a lot of phone calls I found a place that has it.

A1 Coupling and Hose in Eugene, OR 541-485-7133
You need 18" of RFH-7 hose if you have a rig like mine.  It only cost about $11 + shipping.

This was not easy to replace.  The wire in the old hose had rusted to the stack and it would not come off.  I cut the wire with a grinder so I could cut peel the old material away and shoot some power blaster in there and expand the old hose end.

I vacuumed pieces of the old hose out of the air filter.

Putting the new hose on was harder.  The stack is slightly over 7" diameter, so the new hose didn't want to go on.  I used band clamps to pull the slotted end in a little bit while using some channel lock pliers to bend the ends in to reduce the diameter. 

Then I cleaned off everything, smeared a bit of 30-weight oil on the end of the stack and the inside of the pipe, shoved it up as hard as I could onto the stack, while rotating the hose counterclockwise so the wire reinforcement "screwed itself on" to the stack.  But pushing on the hose makes the ribs collapse, keeping it from going on further.  I relaxed the hose while using my fingers to push then portion of the hose already on the stack upwards, working my way around.  It finally went on.

The air filter inlet is not oversize, so it went on a lot easier.
Glad that worked out for you, big difference $500 vs $11.

When I had to replace the flex on our Winne it would have taken more than 6 feet so I replaced it with 6in PVC sewer pipe. Works better, looks better.
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