marine magic doser not working

[rocksteveo]

so i have a 2 week old marine magic 3 pump doser and it was working great for the first 2 weeks then pump A started making grinding noises and not pumping at all. so i replaced the motor with the extra one given and same problem, the i swithced the white front peice and still same problem. i checked the lines to see if there was a clogg or something and nothin. not sure whats going on here and im lost at the moment, any help would be great thanks in advance steve

[FragIt Dan]

Try switching the heads between two channels to see if it is the head. If it turns out to be the head, they come apart pretty easy. The grinding sound makes me think that would be the culprit, but if it isn't, I have 3 of those dosers and have to replace the tubing inside the head every few months as it cracks with time. You can end up with a pretty big mess when this happens, so careful where you put the doser. When the line cracks, it ends up not pumping anything into the tank, so this might be the problem. I posted tear apart picture steps to the head in another thread several months ago, but it's pretty easy.
Dan

[Ross]

Originally Posted by FragIt Dan

I have 3 of those dosers and have to replace the tubing inside the head every few months as it cracks with time...
...I posted tear apart picture steps to the head in another thread several months ago, but it's pretty easy.
Dan

Got a link?

[FragIt Dan]

Not sure what the rules are on this...
http://www.reefcentral.com/forums/sh....php?t=2123530

Apologies if I am not supposed to post links to the 'other guys' . I have a little something for Brad anyway in case I need to buy my way out of it

[Cal_stir]

it is critical that the motor shaft and rollers are clean all dirt, dust, oils,etc.

[Smudge]

What tubing (for inside the head)did you use? Where did you get it from. How long do your pumps run a day?

[FragIt Dan]

Originally Posted by Smudge

What tubing (for inside the head)did you use? Where did you get it from. How long do your pumps run a day?

My pumps run for about 300 seconds on S4/day in a position approximately level with both chamber and hose outlet.

The tubing has been a nightmare to find, I have yet to find a source and am considering requesting a batch from Marine Magic to send out to people as needed.
What works (read warning below): use the original soft tubing that the pump comes with. I think this is supposed to be used to run a line from the head to the dosing chamber as it is 1/4" instead of 1/8"(?). Because it is wider than the tubing that runs through the head, you will need to get a standard air hose coupling (instead of the adapter that comes with the doser). This also removes the need to find those little, VERY fragile adapters.
WARNING: Because this solution expands the diameter of the tubing in the head, expect the head to pump a significantly greater volume, leaving you vulnerable to OVERDOSING your tank. Measure the new volume being dosed and adjust accordingly.
What DOESN'T work: I sourced some intravenous tubing from a medical supply place that appeared to be identicle to the stock tubing in the head. I couldn't get suction using this tubing despite thorough testing. Others may find a slightly different version that works which would be of interest to me. I have also broken a few of those little hose coupling adapters and can't find more, so using a standard size tubing solves that issue too.

I also have not wanted to try standard air tubing due to the stiffness. I suspect the additional stiffness would add substantial wear to the pump motor, if it would even work at all.
Dan

[rocksteveo]

the pump onlys runs for maybe 2 minutes a day, its only 2 weeks old, ive switch the heads with the new one given and still same problems, the tuning is all original stuff, its wierd just pump a is doing it

[FragIt Dan]

I would contact Marine Magic... sounds pretty clearly a warranty issue.

[rocksteveo]

thanks for your helpdan, i just emailed them now , hopefully i can get this figured out.