diy overflow

Steve_the_nucks_fan · #1 03-08-2010, 08:40 PM

umm ok i'm kinda confuzed on what you mean by vent hole.. lol

banditpowdercoat · #2 03-08-2010, 08:45 PM

OK, refer back to the pic posted earlier in this thread.

See the vent hole shown? this is for a siphon break. It lets air in and when the level of the tank drops below this, it lets more air in, causing the siphon i the downpipe to be lost BUT it keeps the water in the overflow pipe over the side of the tank, so when tank level rises above this vent hole level, the drain will automatically start

Without it, the overflow will completely drain the tank to the intake level, where it sucks in air, just like your Youtube vid does. Start with a 1/8" diameter hole and see how it works, if still same, try 3/16" What some people do is put a piece of airline in there and a John Guest valve, and can vary the valve depending on drain requirements. But fiddlin with drillbit holes will work good too

Steve_the_nucks_fan · #3 03-08-2010, 09:08 PM

ok here is another picture to see if i understand what your saying.

banditpowdercoat · #4 03-08-2010, 09:18 PM

Can't read anything on the pic, to small, but the sideways T that goes into the 90 that does on the downpipe to the sump. Between the T and the 90, drill a hole on the top of the pipe. 1/8" to start. this is a siphon break. I have never made a overflow like you have there, but I know you need an air inlet. Acctually, looking at that Drill the hole in the cap that you filled the pipe up with.

Try it first Without the cap on the top of the T, I bet it just may work fine without that cap, Fill it up, and then open valve and see

Steve_the_nucks_fan · #5 03-08-2010, 09:23 PM

Ok I will try with out the cap and see what happens and then go from there. Thanks so much for all the help.

banditpowdercoat · #6 03-08-2010, 09:28 PM

No problem, I know it may sound strange, drilling a hole in somehting that's draining water, but sometimes they drain water TOO well LOL. need some air to slow them down and equalioze things

Let us know how it works. It may be noisy with no cap, so thats why you vary the size of a hole in it, to allow just enough air, but not get that toilet sucking noise

golf nut · #7 03-08-2010, 09:42 PM

I suspect you are not priming at all, I don't care how you force water in the bubbles have the capacity to remain in the top of the U, drill and tap and install a john guest fitting in the first u tube, fill as normal then draw the remaining air out of the top of the U then submerse the JG tube below the surface of the water and you should be good to go, the principle on this system is sound.