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Liquid Cooling Pump Not Pumping

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Zombie01

Registered
Joined
Mar 25, 2011
Location
Missouri
Hi all,

I have recently purchased parts to build a liquid cooling set up. I received them all the other night and began the assembly last night.

I started by assembling everything on my bed and "jumped" the 24-pin mobo connector with a paper clip. It worked like a charm for about a half hour, no leaks, and then I decided it was good enough to put into my system.

Well after getting everything into my system and hooked up (hoses, fittings, clamps) I tried to jumper it again only this time the PC just powered on and the pump did not.

The res is full of liquid, no kinks, and the flow direction is correct. The pump is the MCP655-B and I have the top barb going to my radiator and the side barb going to my reservoir.

Hopefully this is an issue someone has encountered before and will be able to help me. Thanks guys!
 
I thought the top on that was intake and the side was 'exhaust'? There is an arrow on the pump that shows the proper flow. The res should be right before the pump in the loop.

As posted, your top barb (if iw as correct and it is an intake) is taking from the radiator.
 
Hmm...looking at a picture of it (at work ftl) there is an arrow on the top barb that is pointing upwards.

Does that mean that that barb is the exhaust barb and should be going to the radiator like I have it set up?
 
Yes.

That doesnt solve your not pumping issue I wouldnt imagine but at least you have the flow correct. Is the pump even turning on?
 
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No I don't believe so. This is my first time LC'ing anything so I'm not very up to date with all of this stuff but it doesn't appear (or sound) like the pump is even turning on. If it was getting power would there be water movement somewhere or even a noise?

When I had it powered on my bed it was very silent, outside of the water flowing into the res, but other than that it wasn't making a ton of noise.
 
To be honest, I'm sure I did at one point while getting enough fluid in there. But if I did at any point run it dry it was for a second or 2, just until I could pull the paper clip out and add more fluid.
 
The pump will be warm and will vibrate some and you will be able to see a bit of a ripple in the res (not much mind you)
 
OK. I'll check that when I get home tonight. I was thinking of just un-hooking everything from the PSU except for just the pump and see if that would fix it.

I'll try and pay attention to see if the pump gets warm and the Jurassic Park glass ripple in the res :D

Outside of those, do you guys have anything jumping to mind as to why it would work outside of the case and not in?
 
With that pump you may actually have to put your fingers on the motor end to tell if it's running. I run MCP-655's and, at P4 setting, they're the same as the 'B'. When turned down that low they're pretty quiet and, if the loop is bled, the noise from fans may override any noise the loop is making - but you should still be able to feel it running. (Even on P3 I can feel mine, though it's faint.)

If you check with your fingers and it's not running I'd try plugging a fan into the same Molex the pump is plugged into just to make sure it's delivering power. Other than that I can't think of anything that would cause a problem with the pumps. I've had my MCP-655's running non-stop over four years without any problems. Generally, they're very reliable pumps, which is why we often suggest them.


BTW - Your routing is correct, the top barb is the outlet. The impeller on the MCP-355, which many guys on here use, is turned 90 from the MCP-655 arrangement so they often get the flow direction on the MCP-655 confused. ;)



PS
Thinking about it, I've got an MCP-355 that I sometimes have to tap to get running. Never figured out what makes it that way but, if nothing else, you might try that on your pump.
 
Good deal. Thanks guys. I hope that it's not defective as it was working an hour before I put it into the case, but thats usually the way these things go.
 
If it turns out to be something like that I would also follow the advise in that thread and hook the pump RPM sensor up to your board as a monitor with auto-shutdown turned on ...
 
Absolutely. I hope it's something I'm able to fix when I get home.

So if it turns out that I plug a fan into the molex connector that the pump was connected to and it works then the pump is shot?
 
I'd still plug the pump back in and to make sure you didn't just have a bad connection the first time. I'd also feel the motor end to make sure it's not running. You may not be able to hear it running but you should be able to feel it running.
 
pull it out, check it externally, then RMA it, if you got a bum unit it's on the company to replace it.
 
Yea I've already got an RMA number from the company just incase I need to send it back. Hopefully it's something simple but an RMA might be worth it to then get a reservoir and pump that will fit a little better than what I've got :D

Sometimes it's just too much fun spending money and driving the girlfriend nuts.
 
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