Help me with my leak!
 

Hey,

I can't find my damn leak!

I have an eheim 1250, maze2, a gpu block for my geforce 3 from dangerden and a heater core from autozone. Silicon 1/2" tubing and metal clamps on all, all tight. I built an airtrap that is connected to the eheim using clear pvc. The trap rises about 4 inches above the return with a plastic cap. I lose about 2 inches a week. I have blacklights installed and dyelight and cannot find any leaks anywhere. I have even used paper towels to try and catch any drops which would show up with the dyelite.

Any thoughts? System has been running for almost 6 months.

I read on the forum while searching for leaks that one guy had a similar problem and it was his cap. Should I use silicon threading on it?

Also, I was thinking what about that radiator sealant used in cars - safe/ or will it hurt my pump/system? Anyone ever try it?

Thanks - Garetjax

I wouldn't try sealant. it'd damage the pump.

If you don't have a leak that you can see, you might be loosing coolant by evaporation. You don't want to seal the res, but you can put a floating lid, to minimize the evaporation.

Bigben2k,

Any leads/more info on a floating cap, I never heard of it but am willing to try anything.

Thanks - Garetjax

It's pretty easy, just find something that floats (ball or styrofoam) and stick it down the res. The idea is to cover as much of the surface of the coolant as possible, without restricting the float from going up and down.

Why not?

The volume of coolant will change with the temp. It's good to allow the air in the res to flow in and out. It's not necessary to seal the res.

There is an instance where you might want to seal the res, and that's where it is not at the top of your system. It'll work either way, but if you spring a leak anywhere above the res, then everything would flow out of the res, and spill in your case.

OK, now I gotcha. I'm using an outside electrical junction box for my res at the moment, with the lid and gasket. But it's not air-tight. So I guess it serves the same purpose. But it's also at the top of my system.

Bigben2K,

Do you really think it is evaporation causing my water loss - tbru the cap in the top of the filling tube/res? It is a plastic screw on that is pretty tight. They only place other than there could be a leak is the rad but there is never any sign of it under it (checking with black light/dyelite).

Garetjax

My res is completely airtight. I have never had a problem.

Here is a crummy pic of my res:

http://www.utcorpleague.com/images/104-0401_img.jpg

Whoa... I had to step away from my monitor to see that!!!

That amount of loss could be from evaporation, but if you have a screwed on cap, then it's more likely that you have a leak. You'll have to look closer...

You can't find any leaks you say. Have you considered, that you still have air in the system, it could be that your air trap doesn't work too well, try moving your case a little while the pumps is running, if you can hear anything from the pump, that could be cavitation from air bubles still in the system. So maybe you just bleed air very slowly.

Another thing to note is that if your threads arn't sealed, you can have air evaporate out of the seals slowly. A simple pipe thread sealent would do the trick, but you can't use it on wet threads.

Also, having a sealed res is no problem, yes, water does change volume slightly with temperature, however, air is compressable, so the air will just compress, no big deal.

Hey,

I moved my case around and no noise. Besides, I have had this problem since I set it up and this case has been to several lan parties so it has been moved around a lot.

Garetjax

Try putting some plumbers tape on your cap threads and then tightening it. That will make sure that you have a much better seal than just pipe threads. BTW I loose some water in my res. as well, about 1/2" per week due to evaporation (need another radiator to keep the water temp below 30C to avoid that)
One thing to check is to take the cap off your res. and look inside the cap for water dropplets. That will tell you if water is evaporating or not and then depending on how much your threads dont seal, how much water you are loosing.

Just a suggestion.

Hey,

I just checked, no water droplets on the bottom of the cap. Totally dry. Now does that mean it is evaporating or not evaporating?

Garetjax

It would mean that it is not, according to jtroutma (who I trust).

You just might have air coming in and out of the system. If you can't find the leak, then just drop it!

That usually means that it is NOT evaporating but some evaporation may still be present (however not enough to loose a significant amount of water)

hmmmmmmmm..........

I would check ALL connections again and reclamp them again. Maybe even do what BigBen was suggesting and pressure test your radiator with a bike pump.....

what pump do you have? is it sealed?

Hey,

Eheim 1250, yes its sealed, really well. My clear pvc airtrap/fill tube is attached to it with pvc cement. I then put a layer of plumbers goop around it for added protection.

I have dyelite and black lights all in my box and never see any leaks.

I am really stumped.

Garetjax

On PVC? I doubt it will help much.

Those pipes don't look like you used PVC cement, at least the stuff I've used. Did you use primer as well?

Also I'd check the gearbox clamps. IME they tended to leak ever so slowly. My old system bleed away about 3/4 an inch a week until I replaced them with better clamps. The problem was they clamped really tight, but not evenly and some coolant slipped by under the actual box part.

air is evaporating through your silicone tubing

Redleader,

I used regular pvc cememt to connect the parts, but when I tested the system in the bathtub for 2 days it leaked - the pvc airtrap leaked - so I applied a coating of plumbers goop around the outside of the joints and that stopped the leaking.

Brad,

Does that new type of tubing - tygon allow vaporation as well?

Garetjax

Nope it's special to silicon. Actually silicon tubing is meant to carry gases, not liquids because it's porous (and not chemically stable / inert). Ppl use it in watercooling because it's very soft and bends well.

Hmm,

I think I'm gonna switch to tygon, if I'm gonna redo all my connections I might as well just switch tubing to see if it is evaporating from the silicon tubing.

R-3603 bends better right? I have some tight bends going from my gpu block to a T.

Garetjax