T-Line problem

I'm having a problem with my T-Line. I've set it up to be outside the case, at the very top, like this.

........Top of Case
.....____________
.L=|>-------E
.....|...........|
.....|RAD----T----PUMP
.....|
.....|
.....|
.....|
.....|....Other Components
.....|
.....|

Ok, I'll try to explain. First, ignore the .'s. The "L" at the top left is a little elbow connector that comes out of the back of the case. That's my fill point. There's a barb that comes through the case on the other side - the ">". From there, 3/8" tubing runs to the "E" on the top, which is actually an elbow. Then it goes down into the rest of the system through an actual T fitting - the second, or lower T. That goes to the right into the pump's inlet, and goes to the rest of the system, etc., to return through the radiator.

My problem is, when I try to fill from the little elbow joint (The "L") the water just sits there. It won't flow down into the rest of the system. I think the problem is that air can't escape back up the elbow to let water flow down. Water doesn't even trickle through that horizontal strech of 3/8" tubing (the "-----"). It just all backs up at the elblow.

I would hate to cut another hole in the back of my case to add an air line, so I was wondering if it would work to just do this:

...........Top of Case
.........____________
.L=L=|>-------E
.........|...........|
.........|RAD----T----PUMP
.........|
.........|
.........|
.........|
.........|..Other Components
.........|
.........|

Add a T instead of the fill elbow, and attach an elbow to that. That would give me two fill holes that go into the same line. Anyone think it would work? I could really use some help here, because I'm a little lost at this point.

I'd get rid of the one elbow inside (the E one). Use one solid piece of tubing, and make sure it's short enough so that water from the filler fitting doesn't need to run uphill at any point.

You could also first try to shorten that piece of tubing between the T and E, maybe a half inch at a time. That may get better results.

Sharp corners are nice for apearance, but they can mess you up sometimes too. Add the small ID of the fitting with a lower surface tension from additives in your water, and you can get bubbles that acts as a ball valve for a time, and stop the water and air from trading places.

Have fun!

*it 'll sound stupid, but if you applied suction to the elbow on the outside, the 'airlock' would break and allow the water to flow down, if that's the problem.

Alright, that gives me some stuff to try. Thanks a lot! I'll put up some results later today...probably more questions.

Mmkay...still not working. I tried shortening the tube between the T and the E as much as I could, but that didn't do anything. The water from the fitting doesn't need to run uphill anymore, I know that much.

I also tried the setup in the lower picture - adding another T so that I have to inputs to the same tube. That didn't help either, filling from either of those points still trapped water right at the "L's". In fact, the water isn't even going through the barb - the ">" thing. I'm stuck at this point...any more ideas? Are they just too small, and will I have to add another T-Line?

I'm starting to regret getting rid of my reservoir....

Played with it some more, and I give up. I think I'm just going to use a normal T-line like a normal person.

Is there any way you could slip a really narrow tube down into the main tubing? This would give air an easy escape. Maybe something like ice-maker tubing?

I think it'd be too thin even for that. Images of catheters...

The tube would have to be smaller than 1/4" OD to even fit. I just gave up, and I'll use a 5/8" T line coming from the T in the picture.