Strange happenings with my T-Line

The t-line was for the longest time 75% full. Then it started blowing the top off and it would run 95% full. Then all of a sudden it started going 50% full.

Now the strange stuff begins With my top on for a while the T-Line will completely empty! When I remove the top it exhausts some gas and re-fills to about 50%. Putting the top on repeats the cycle.

So where is this mystical gas that's building pressure in my lines coming from? I do use a copper and aluminum mix in my system but there's plenty of anti-freeze in there as an anti-corrosive. I don't think this is the problem though - I ran it for weeks 24/7 before this problem arose. Is it possible to have an anti-leak; one that lets air in without letting water out?

Here's my WC setup:

87 Chevette core
Danner 3 pump (sealed with silicon)
Z4 GF3 waterblock
Z4 gearwheel CPU waterblock
Clearflex w/ hoseclamps

Any ideas?

--Illah

The only thing i can thnik of is that some chemical reaction is going on ang gas is one of its results. Possibly gas started to gather in WB and was trapped there. It pushed water aside, thus water level in T-line got higher. Then gas was washed away, got to T-line and pushed the liquid down, thus water level droped.
What reacts in the system i cannot guess. How long the system runs in exactly the same configuration?
May be you should try changing the additives to water.

Mine was doing this when the temp of the water would change. If I leave my fans off and just run the pump the water would eventually get low. I woud think you are seeing the same thing, its just heat.

OK, I do see a bubble dislodge when I vent the gas, but it has been happening for over a week now. As for the heat idea, I doubt it cuz I run SETI. It's at a constant load temp (except when I start playing Splinter Cell, but the problem happens regardless of gaming).

So far theres no temp change or leaks though. I just want to head off a problem before it's serious though.

--Illah

I saw something similar when I was using a T-line. there could still be air trapped in your radiator/heatercore
Try rotating your rad around (flip it upside down, turn it on its side, etc, etc...) while tapping on the side of it with something solid like a rubber mallet.

Maybe you're seeing some electrolysis?

If there is any difference in voltage between two metal components that touch water, you could see some of the water get split into hydrogen and oxygen gas. Does the air have an odor? Have you tried igniting it?

So, when you have the lit on the t-line, it is air-tight. The fact that the fluid level goes up when you remove it tells me that the system is under (possible very slight) pressure. What is likely happening is that there is an area in your system that is behaving like an open resorvoir. When you open the t-line to release some of the air, the pressure level between the t-line and the "open resorvoir" is equalizing. Thus you see the fluid level rise.

To demonstrate this, try taking a length of tubing (at least 1 foot, more is better). Bend it into a "U" shape, with the open ends pointing up. Put some fluid into the tube. Notice that the water level equalizes between the two legs of the tube. Now seal one end. Raise one end of the tube relative to the other. Notice the relative water levels change? Now, with the one end still held higher than the other, unseal the sealed end. The uneven water levels should equalize.

I've noticed the level fluctuates in my T line, a symptom of heat. The air in your system (in the T line as well as in the water, albeit at a microscopic level) tends to expand with heat faster than the liquid itself, a lot like a lava lamp.

What I did was fill cold, and hose clamp the cap on the T line. All remaining clamps were hose clamped and air-preasure tested to ensure that none would "blow off" if it built up too much preasure.

I made the cap from a brass Barb-NPT adapter and a brass NPT cap, with teflon tape on threading. This worked for me, but YMMV.