Need a little help in understanding the layout of my freshwater tanks.I have two tanks 55 gallons each approx. There connected together near the bottom with an approx. 1 1/4" hose. Without pulling them down I cant see all the connections, but it appears each tank has a couple vent lines in the top, I believe the fill line comes into one of them and flows into the second via the 1 1/4" line. I also believe the rear tank has a 1/2" or so line that runs to the pump. That 1 1/4" line that connects the two tanks is close to 1 1/2" up on the sidewall of the tank. That being the case that front tank always has at least and inch and a half of water in it. Is that common or is there a suction line going into that front tank that I'm not seeing. Seriously considering pulling the tanks out and putting the connector line down on the bottom of the front tank and raising it up a little, (or dropping the rear tank down) so the water has a chance to flow into second tank. Any thoughts?2008 Cyclone 3912

I don't know about the 1 1/2" but you cannot put the fittings exactly at the bottom of the tank. Is that small amount of extra water capacity enough to go through all that work. Ying and Yang, is it worth the effort.

Jim Cindy wrote:I don't know about the 1 1/2" but you cannot put the fittings exactly at the bottom of the tank. Is that small amount of extra water capacity enough to go through all that work. Ying and Yang, is it worth the effort.Why cant I put it in the bottom of the tank? Without measuring (I'm at work) I would guess the tank is about 8 inches tall, that means almost a quarter of the capacity is left in there, with no way to drain it. Sets in there all for several week/months between dry camping trips could get pretty funky I would think :p

mr. old style wrote:Jim Cindy wrote:I don't know about the 1 1/2" but you cannot put the fittings exactly at the bottom of the tank. Is that small amount of extra water capacity enough to go through all that work. Ying and Yang, is it worth the effort.Why cant I put it in the bottom of the tank? Without measuring (I'm at work) I would guess the tank is about 8 inches tall, that means almost a quarter of the capacity is left in there, with no way to drain it. Sets in there all for several week/months between dry camping trips could get pretty funky I would think :pIs there clearance to bring a line off the bottom of the tank and then tie it to the other tank? Keep in mind water does not flow uphill.

Lantley wrote:mr. old style wrote:Jim Cindy wrote:I don't know about the 1 1/2" but you cannot put the fittings exactly at the bottom of the tank. Is that small amount of extra water capacity enough to go through all that work. Ying and Yang, is it worth the effort.Why cant I put it in the bottom of the tank? Without measuring (I'm at work) I would guess the tank is about 8 inches tall, that means almost a quarter of the capacity is left in there, with no way to drain it. Sets in there all for several week/months between dry camping trips could get pretty funky I would think :pIs there clearance to bring a line off the bottom of the tank and then tie it to the other tank? Keep in mind water does not flow uphill.But it does flow onto the ground if you rip the fitting off.

Drill and tap holes in the bottom of both tanks, thread in elbow fittings and add a hose between. The distance the loop is below the tank doesn't matter. The bottom of the tank that you want the water to flow from needs to be the same level or higher than the other. You can encourage the process by leaving the trailer slightly nose high or low as the case may be.

Fresh water tank question | Good Sam Community

honda4us
Explorer
Jun 06, 2013
spin welding They should be able to help you out, note you do need a 1 HP or larger router to install the fittings.
mr__old_style
Explorer
Jun 05, 2013
high desert wrote:
mr. old style wrote:
Jim Cindy wrote:
I like high deserts solution to use the tank drain lines for pump supply. Should make all the water capacity usable.

Therein lies the problem. The front tank has no drain line. The only way for water to get out is through the connection to the other tank which is 1 1/2" above the bottom (measured) making it theoritaclly(sp) impossible for it to drain.

I would definitely add a drain to that tank. You can use a spin weld fitting that will make the job fairly easy.

That would work do you have a source for the fittings?
high_desert
Explorer
Jun 05, 2013
mr. old style wrote:
Jim Cindy wrote:
I like high deserts solution to use the tank drain lines for pump supply. Should make all the water capacity usable.

Therein lies the problem. The front tank has no drain line. The only way for water to get out is through the connection to the other tank which is 1 1/2" above the bottom (measured) making it theoritaclly(sp) impossible for it to drain.

I would definitely add a drain to that tank. You can use a spin weld fitting that will make the job fairly easy.
Bonefish
Explorer
Jun 05, 2013
mr. old style wrote:
I have the bottom off mine also, and the line is 1 1/2" up the side of the tank that part I have measured. I just dont know what there thinking when the design/build these things. The drains for the plumbing come out right in the middle of the trailer right above the middle axle, not exactly easy to get to. Would it have been that costly to use an extra 4 ft of half inch house and brought them over within reach of the side wall :h

The lines to drain the tanks should be near the bottom edge of the tank or in the floor of the tank. Any plumbing for access to valves should not be in or near the wheel wells. Reason is if a tire blows or separates the flailing tire tread will rip out any thing it wraps around or hits. It would most likely rip the plumbing out of the tank.
mr__old_style
Explorer
Jun 05, 2013
Jim Cindy wrote:
I like high deserts solution to use the tank drain lines for pump supply. Should make all the water capacity usable.

Therein lies the problem. The front tank has no drain line. The only way for water to get out is through the connection to the other tank which is 1 1/2" above the bottom (measured) making it theoritaclly(sp) impossible for it to drain.
beemerphile1
Explorer
Jun 04, 2013
If you want to modify in order to get the full amount of water, I would leave the factory piping alone. Drill the bottom of each tank and install 1/2" brass fittings. Run a 1/2" poly tube between the tanks for balancing. You don't need it to flow fast, you just need it to flow.
64thunderbolt
Explorer II
Jun 03, 2013
my 122 gal has a sump about 6" square and 3" deep on the end. The supply line is installed there.
Jim_Cindy
Explorer
Jun 03, 2013
I like high deserts solution to use the tank drain lines for pump supply. Should make all the water capacity usable.
mr__old_style
Explorer
Jun 03, 2013
Lantley wrote:
mr. old style wrote:
I have the bottom off mine also, and the line is 1 1/2" up the side of the tank that part I have measured. I just dont know what there thinking when the design/build these things. The drains for the plumbing come out right in the middle of the trailer right above the middle axle, not exactly easy to get to. Would it have been that costly to use an extra 4 ft of half inch house and brought them over within reach of the side wall :h

The tank is directly above the axle to allow the axles to carry the weight of the water. Access is secondary to structural integrity.

The drains I'm talking about are probably at least 5 feet or more behind the tanks. Both tanks are well in front of the axles
high_desert
Explorer
Jun 03, 2013
I had the same problem on my Fuzion although on mine there is an outlet to the pump on both tanks. There would still be a bunch of water left in the tanks when the pump would start sucking air.

I tee'd off the tank drain fittings and ran the supply to the pump from there, then plugged the original outlets on the side of both tanks. Problem solved.