air buble in auto-siphon

[hardrain]

I've been getting an air bubble in my auto siphon right where the pump meets the tube. am i doing something wrong that is causing this?

kind of related, I also have a tube that thinks its cool to float on top of the beer instead of staying below the surface...any suggestions on keeping that down? has anyone added weight to the end?

 

[Bobby_M]

It's a good idea to use 5/16" ID tubing on a 3/8" autosiphon cane. You warm it up in hot water and slip it on. The tighter fit stops air from being sucked in. I struggled with the same thing when I started with 3/8" ID tubing and a clamp never helped.

 

[TheOceaneer]

Apologies if this is idiotic/obvious, but are you keeping the source for the siphon well above the destination? I had a similar problem (bubbles) the first time I used my auto-siphon, as I was a.) using the wrong tube, and b.) not raising the source significantly above the destination (I think I sat it on a phone book).

In all subsequent uses, I have placed my primary/secondary on a chair, with the seconday/bottling bucket on the floor. Works like a charm (and goes significantly faster).

 

[hardrain]

is tubing from the hardware store 'food grade'? my LHS only has one type of tube.

 

[Rhoobarb]

is tubing from the hardware store 'food grade'? my LHS only has one type of tube.

Not to my knowledge, no. I've never had a problem w/ 3/8" tubing from the HBS, though. But I found that this helps a lot: slide it onto the racking cane portion at least an inch. Once the siphon starts, pinch the hose for a second just past the racking cane, then let it go. That eliminates any bubbles. If the tubing is worn, just replace it.