Blue-boy height issue on a '70

[rayandre]

So we took our Overlander out for the first time had a good trip overall. I had purchased a 4-wheel Thetford "blue-boy" to drain grey water using a hose adapter cap. I boticed when I tried hooking it up with the provided 24" hose it wa a really tight fit because the sewer cap height was almost the same as the top of the tank where the hose was suppose to connect to. I was able to barely get it connected and after the first day we had a back up of grey water in the tub. There was some grey water in the tank but not very much. Luckily I had a long piece of old hose with me and moved the blue-boy about ten feet behind the trailer which also luckily was sloping down hill. After that there was no problem-enough gravity to get it to drain for the remainder of our trip. Is there another way to handle this? I'm just a little concerned if we camp and don't have a spot that pitches downhill away form the back of our trailer. Any tricks to getting these new blue-boys to fit or drain right? I have new axles by the way so I know my AS is sitting about as high as it can without the use of additional blocks.

[Chuck]

I use a length of washing machine hose, which is about 3' long. That gives plenty of flexibility for height/terrain issues. Its ok for it to "loop" if the tank is under the trailer, or in close...as long as everything is lower than the lowest drain in the trailer, it'll work.
You'll get "back ups" if the hose is kinked, or if the tank isn't vented. If air can't get out of the blue-boy, the water can't get in, so you need to crack open one of the openings in the top of the tank.

[TG Twinkie]

I had a similar problem with the '74 Argosy. The heighth of the outlet was not enough to get a good flow with the valve left open. The first time I emptied the grey water tank it was full and backed into the tub. The Blue Boy is 10 gallons (same size as the grey water tank) which made it a challenge. I managed to get enough out of the grey water tank to fill the Blue Boy with only a small spill, maybe a quart; NOT GOOD!
After that experience, I left the valve closed on the grey water tank and emptied it into the Blue Boy every day using a short hose. By leaving the valve closed the tank provides enough head pressure to push the grey water into the Blue Boy when the valve is opened. Then it's just a matter of closing the valve and lifting the hose to drain the remainder into the Blue Boy.
It is a bit of an inconvenience but better than hauling the trailer to the dump station.
Of coarse, one has to monitor the water useage, especially with the tub and shower use.
I suppose one could rig up some kind of pump to do the job, but that seems like more hassle.
Since most of the tank level monitoring systems don't work all that well. My next thought is to try to measure the amount of water removed from the fresh water holding tank. In effect a water meter in the line from the pump.
When the meter reading approaches the 10 gallon limit in my case, I would know it is time to dump the grey water tank. Since some of the water used would have gone into the black water tank, there would be some wiggle room on the grey water and the Blue Boy would not be completely full.
Any additional ideas would be welcome here.
Now to find a water meter.

[Melody Ranch]

I use a 12 ft. hose. That way I can also use it when draining to ground..away from the trailer. I think a 2 ft. hose is way to restrictive.

[1Boyscout]

Blue Boy trouble, it is a big problem on a 2015 too. I have a 12 gal, and it barely is workable. I have a 42 gal from when I had a Box TT, sitting 36 inches off the ground.
It will be in my next garage sale.

[Stefrobrts]

Maybe our blue boy is lower to the ground, but it is definitely lower than the shower (which is where stuff backs up to first when there is a backup). We do use a longer hose, about 4 ft long, because the blue boy cannot go directly under the outlet, it sits out a little further, so the hose is not kinked or anything. As long as the blueboy is lower than the showerpan it should all end up in the blue boy.

Don't forget to remove the other plug on your blueboy as well for ventilation, so air can get out as water goes in, else that will also cause a backup. We made that mistake on the first trip of every year three years running! I think we'll never forget it again!

[Tom Nugler]

I have a Thetford 12 gallon 2 wheel “Blue-Boy” and, yes, they can be a PIA at times.
The better half does a lot of food prep during the Rallys. The most annoying problem was the hose getting plugged up with food scraps. I know, user error. I have a 4 foot piece of ¾ id hose which works OK.
The collector on the TW drains straight down. If you have the same set-up this could work for you. I cut about 5 compressed inches off the slinky and fit adapters for the trailer and the tank. If there is enough clearance now you have a clean, sealed shot straight down.

Tom