Can you use flex exhaust hose to remote the gennie exhaust ?

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patsdad

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I'm thinking that getting the noise of the exhuast outlet, and the fumes, away from the camper would be nice.  And, I see that the approx 4" square hitch mount tube that runs across the back of the camper would make a handy conduit for , say, a 2" round flex tube, and a little heat wouldn't bother it.  But, I don't know if long runs of flex hose ( say, 10 ft ) cause enough backpressure to be a concern.  I'm thinking that even if they aren't completely airtight, a little leakage couldn't be worse than having the main exhaust exit around the back of the camper, as it does now.

Perhaps this is a very old idea, but it just occurred to me as I was under there, monkeying with the gennie exhaust so it doesn't cause a fine hitting the rubber mud flaps.  Anyone tried this ?

Besides backpressure, it could be that the result would be a whole long tube making noise, instead of just one point . . . .

 

Tom

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Why not buy a Genturi that vents the generator exhaust above the coach. I can't promise it will necessarily reduce the noise though.
 

Ned

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As long as the hose is sufficiently large and there are no kinks, it will work fine.  But as Tom suggests, get a Genturi, it puts the exhaust above the roof line so it doesn't matter which way the wind blows.
 

Jim Dick

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Hi patsdad,

We used a flex hose on our first motorhome. It was one of those that garages use to vent the exhaust of cars outside during the winter months. It worked fine but was a pain to set up. The Genturi works great and is easy to use. We've used one for several years now.
 

Jeff

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I tried a flex hose but had two problems. First it was too hot to attach to side of coach so I used it to run the exhaust to the rear of our Pace Arrow. Also I started with about 18' that was the same ID as the OD of the exhaust pipe and it seemed to create enough back pressure to pull the Onan down. I cut it to 8 feet and it seemed better.

A Genturi is oversized to allow a venturi affect to draw cool air into the pipe so it avoids both these problems.
 

John From Detroit

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Using an exhaust hose lying on the ground does seem to help, however since the exhaust is hot, and at ground level it's going to rise, it can easily rise up into your, or a neighbor's motor home

Now, using the Genturi it rises up over the roof before it goes anywhere else, being hot, it continues to rise and thus it's up up and away and nobody gets to hear that loud BEEP BEEP BEEP from their CO detector
 

Jim Godward

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As an alternative, make your own version of the Genturi.  It is fairly easy to do. a exhaust elbow of the size to fit over the generator exhaust, some 3" pipe, not PVC the other higher temp stuff-can't remember the proper name!  Some sheet metal to attach the pipe to the elbow and a couple of screw eyes for attaching the whole thing to the MH via a couple of big suction cups.  Oh yes, some rivits or screw to hold the whole thing together.

Should cost less that 1/2 of a Genturei and it works fine.  Several friends have them.  I have a Genturi, but then I didn't pay for it either.  VBG
 

Ned

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I believe the Genturi uses polycarbonate tubing.
 

patsdad

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Thanks for all the good info.  I may just buy the Genturi ( their website says yes, it's polycarbonate tube ), or attempt a homemade version.  If I can figure out how to avoid making it look too hillbilly, I may run it across the back through the hitch mount, and then up using the ladder as the mount, with a Genturi-style breather joint at the base.

Thanks for the suggestions . . .  good stuff.
 

Jeff

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patsdad said:
Thanks for all the good info.  I may just buy the Genturi ( their website says yes, it's polycarbonate tube ), or attempt a homemade version.  If I can figure out how to avoid making it look too hillbilly, I may run it across the back through the hitch mount, and then up using the ladder as the mount, with a Genturi-style breather joint at the base.

Thanks for the suggestions . . .  good stuff.

We had friends buy black tubing locally to make their own version of a Genturi. Worked great for about 30 minutes and then folded over like a limp noodle. Evidently polycarbonate tubing is a special order item.
 
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