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createdlight
06/11/2011, 07:00 AM
trying to figure out why i have a big decrease in water flow from my main sump return pump, i thought maybe something like a snail got in it clogging up the impeller. so i removed the pump ,and the impeller and pipes are clear, next checked the overflow drain tubes, and these are also clear.
system 210 tank, pre drilled (two down two up) pump is a dart snapper super dart...This has been in operation from about 12/10/2010, and it always had very good pressure coming out of the four return nozzles. Nothing has been added to this system to tax it of pressure/flow. any ideas?

thanks gary

MarcoPolo
06/11/2011, 07:06 AM
Gary, is the impeller and pump interior clean as in "no calcium" build up on it?

createdlight
06/11/2011, 08:03 AM
Gary, is the impeller and pump interior clean as in "no calcium" build up on it?


without taking the impeller housing apart, and just looking through the intake and output cavities, i see no calcium at all, only a skim coat of slime.

spieszak
06/11/2011, 08:14 AM
can you cap/clamp the return hose on the pump and then run it through a short new small tube? That'll tell you if its the pump of the tubing...

lordofthereef
06/11/2011, 08:19 AM
can you cap/clamp the return hose on the pump and then run it through a short new small tube? That'll tell you if its the pump of the tubing...

:thumbsup:

Also, if you have the thing apart (which is sounds like you already did), you may as well give it a good acid soak (some like white vinegar+water, some muriatic acid+water) and then a good scrub. Make sure any rubber/O-Rings are removed before soaking or you will ruin them. This should be done every 6 months anyway, IMO, so you are coming up on time to get that done.

MarcoPolo
06/11/2011, 08:20 AM
If the pump is operating normally, but you observe decrease in flow, then you would also observe different water levels in main tank and sump. If that is not the case, it can only be pump. You mentioned this has been running since Oct last year, thus 8 months. Good time for a nice clean up. What I normally do is take pump out, soak impeller and pump interior in vinegar for 15-30 minutes, in meantime clean well the rest of pump, eg grid inlet, etc. Then re-assemble and pump performance noticeably better. You should do this regularly, would say every 3 to 6 months, good practice for ensuring long life of the pump. Even if this is not your problem, good idea in any case to clean it up. Follow my suggestion and let's see if in an hour things get better :fun4:

createdlight
06/11/2011, 08:23 AM
can you cap/clamp the return hose on the pump and then run it through a short new small tube? That'll tell you if its the pump of the tubing...

I'll be doing a water change today, and i have a tee off from main return line plumbed to sink, should be able to tell then ....i hope

just a thought , does the impeller wear out, so as to decrease the water flow rate? if so how often? it's only been about 7 months

thanks gary

MarcoPolo
06/11/2011, 08:28 AM
It will not wear out if regularly maintained. If debris accumulate or sediments get in, it can damage impeller and pump interior with scratches which reduce efficiency and can cause overheating, noise and vibrations. That's why you should check & clean regularly :fun4:

dwa_jeff
06/11/2011, 08:35 AM
In my experience with dart pumps, anytime i have a decrease in output its almost always because something is clogging the impeller. The grooves on the sides of the impeller wheel can catch a lot of debris and even the smallest particles will have a big impact. i usually take a small pipe cleaner brush and run it through the grooves. usually runs MUCH better after that.

createdlight
06/11/2011, 11:51 AM
thanks all for the very informative information. The pump came with an extra impeller, maybe i should just change it out, while letting the old one clean up.

capecoral
06/11/2011, 07:20 PM
Vinager can hurt the rubber seals?

createdlight
06/11/2011, 07:27 PM
well i did the water change, So i was able to cancel all the return plumbing out, and using main pump to drain water into sink, we have it plumbed this way, couple of valves and into the sink it goes.... problem is the pressure seems very good dumping out into the sink. has to be a restriction on the return plumbing, but where would be the most likely area? the return nozzles?

dwa_jeff
06/13/2011, 06:25 AM
If you have the loc line return nozzles that have the ball valve on them (the type that thread into a bulkhead), these often get calcium deposits that will restrict flow and they need to be cleaned regularly. A few of the systems i take care of have these and they need to cleaned at least once a month to get them to flow the way they should.

If the flow from the pump is fine through the other plumbing than it almost has to be somewhere in the return line. I would try to clear the line if its possible . If you can remove the plumbing, (cause you wouldn't want whatever is in there to end up in your pump) you could try to force some water through it in reverse to dislodge whatever might be clogging it up. I've had to do this a few times and it usually does the trick. Also a length of flexible tubing could be ran through the plumbing as long as there aren't too many bends to "feel" for a clog. If your plumbing is pvc, this is what i would do. If its soft plumbed with flexible tubing, I'd just replace it.