length of evac drain

[suprfst]

Every time I checked the drain it was full so I bought a chunk of clear 5/8 id tubing from ace hardware its about 10" long,I put the original black cap on the end of the clear line to cap it .I checked it at 200 miles(274 mile day)and it was full but normally I see it to have about two to four inches of liquid in it.Im assuming the humidity is why some days it seems to have more fluid than others.This may have allready been covered but I havent seen anything.

 

[rhoag]

This may be a dumb question but, isn't there a oneway type of valve that could be put on here that would allow it to drain but not suck anything in??