Pump not circulating water?!

bikeracer4487

Distinguished
Jan 20, 2009
332
0
18,810
So I recently installed my first water cooling system over the weekend and bought an MCP35X pump since, from the specs I could find, it was one of the most powerful, and I didn't want to have to worry about whether my pump was powerful enough or not. Anyways, I have the tubing routed as follows: pump -> radiator -> CPU block -> GPU Block 1 -> GPU Block 2 -> Reservoir -> Pump. Problem is, the water doesn't seem to be circulating. When I power on the water cooling system I can feel the pump humming along and I can see water being intermittently pulled from the reservoir, but I see these big bubbles in the tubes that don't move unless I lay the case down and back up, and there doesn't seem to be any water reaching the GPU block...not sure what could be causing this...
 

HugoStiglitz

Distinguished
you could have an airlock in your pump.

where the water returns back into your reservoir dissconnect it and give it a suck until you have water coming out (dont swallow obviously)

this should pull water through and remove the air lock from the pump.

sometimes unless you have ALOT of flow airbubbles will stay where they are. but should "jiggle" as water flows past them.

if you cant get water by sucking from the pipe you may have a blockage / kink.
 

rubix_1011

Contributing Writer
Moderator
Sounds like you have a lot of air in the loop...especially since you have your pump pushing straight into your radiator- I'm guessing that you have a big air bubble in there. Also, is your reservoir always full or high enough for the pump inlet to always draw water?