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Old 11-03-2015, 07:54 PM   #1
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Fresh Water Siphoning

We have a 2016 36 CKTS and have only filled the fresh water twice, both times once the overflow begins to run and I shut the fill hose off it continues to overflow for several minutes.

I wish I had a bucket to measure it but I would guess about 10 gallons came out of the overflow line. I wouldn't think this normal, is it?

If it isn't is there a fix for it?

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Old 11-03-2015, 08:24 PM   #2
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If I was worried about losing to much water then I would put a shut off value on the over flow line

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Old 11-04-2015, 01:00 AM   #3
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Mine will do the same if the trailer is not setting level especially if the pavement is sloping to the drivers side.
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Old 11-04-2015, 05:42 AM   #4
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Not trying to be disrespectful but I doubt 10 gallons came out of the overflow. However, it is not unusual for the overflow to continue releasing water for a few minutes before it finally stops.

I'd measure how much actually came out and if it was 10 gallons then something isn't right.

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Old 11-04-2015, 06:53 AM   #5
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I've seen this too on mine. I put the hose in the tank, it comes out like it's full. I look at the tank gauge and it says 1/3. I stuff the hose in the tank and hold it there until I see water coming out the over flow. I pull the hose out and the water shoots out of the tank for a bit and then a big blast of air comes out. Tank now 2/3 full. I do it again and the same story. If I fill at the CG with jerry cans, same story. Ergo, my conclusion is, that the tank vent line was missinstalled at FR and not able to let the air out of the tank at the same rate the water is going into it. It's not totally blocked but crimped. Ill bet that the tank is getting bulged out when the water is going in fast and wants to push the water out when you remove the flow into it. Mine's at the dealer at this time getting the last few warranty things corrected before winter... I hope!
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Old 11-05-2015, 10:13 PM   #6
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Oakman, I took your post to heart and had an opportunity this afternoon to fill the fresh water tank with a few 5 gallon buckets in place.

In a few minutes water began to overflow one bucket was in place it filled in a couple of minutes and I replaced it with the second one. After a couple of minutes I readied the 3rd bucket and just short of the 2nd being full it quit. So I guess you were right it wasn't 10 gallons like I guessed but somewhere between 9 and 9 1/2 gallons of overflow.

Even when I stopped the flow as soon as I removed my thumb it continued, I reall don't want to start removing panels but it looks like it's my next step.
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Old 11-06-2015, 01:53 PM   #7
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There are two fittings (one fill and one vent) on a raised boss on top of the fresh water tank street side and two fittings (one supply and one drain) in a boss on the street side bottom of the fresh water tank. Once the water level drops below the top boss, it cannot siphon any further. Your last test was static, so sloshing can be eliminated. I imagine your vent line is somewhat kinked and when you fill the fresh water tank via the valve in your convenience center, the tank expands like a balloon since the vent cannot keep up with the incoming volume of water. Once it starts coming out the vent line, it continues till the tank returns to it's natural shape accounting for the amount you described. The belly panels can individually be removed so you can fairly easily check for the vent line kink by just pushing the insulation aside once the panel is dropped. If your lines were to be swapped on the tank itself, it would tend to drain the entire tank instead of just @ 10 gallons.

Try filling it again, but only at a slow rate. See if your issue returns.
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Old 11-06-2015, 03:44 PM   #8
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We have never had this issue.. BUT my parents Georgetown would siphon all most all the water out when they filled the Fw tank. They ended up needing to have a shut off valve installed to keep the tank from almost emptying, so it could be 10 gallons.. LOL!

Just do NOT forget to open the valve when filling! They bent a bracket when they forgot to open the valve...

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