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Old 04/11/2016, 07:48 PM   #1
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Join Date: Sep 2009
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Did your skimmer suddenly overflow? Want to avoid premature pump failure? Read here!

Did your skimmer suddenly overflow?? Did your pump fail prematurely? Pump maintenance is extremely important in keeping any skimmer performing at optimum levels. It's also critical in insuring that your skimmer pump doesn't prematurely fail. This goes for any skimmer pump but today we are going to discuss the RD3 because that's what my Supermarin runs with.

First off, the most common reason for skimmers to suddenly overflow is salt creep in the Venturi port on the skimmer nozzle. This can also cause the RD3's controller to display an F8 error. It's a commonly overlooked**part of maintenance. While most of us clean our pumps, many don't think to look in the Venturi air intake ports for salt creep. Salt creep in the venturi port causes an air restriction. The end result is that the pump will push more water into the skimmer resulting in an overflow. Overflows can also be caused by debris or even snail or crab intrusion into the pump. Attached are photos showing salt creep into the Venturi port and also pictures of what a well maintained skimmer pump looks like. This pump is 1.5 years old and just got a quick vinegar bath and good scrub followed by a rinse. Notice that the pump looks like brand new inside and out! I have seen many skimmer pumps both older and newer and they look terrible. I clean my pump every few months and it always looks like new. Yours should too! There is no reason anybody should have a skimmer pump let alone internal pump look like it's never been cleaned let alone fail prematurely due to a lack of maintenance. My go to tools for cleaning my pumps are: Vinegar, a scrub brush, a tooth brush and a skewer to remove any salt and or calcium buildup in the Venturi port. See pictures below. Notice how clean the pump is after a little TLC!

*** Note, if you have a regular Red Dragon (not the RD3 pump) another often overlooked part of pump maintenance is the bearing at the base of the impeller shaft inside the magnet cavity. It's very important that you remove the bearing from the inside of the motor block after you pull the impeller out. Soak the bearing in vinegar and clean it thoroughly. Make sure the little hole that the end of the impeller shaft sits into (when the bearing is seated in the block) is clean as well. A tooth pick can come in handy for this. It is absolutely critical that the bearing be clean so that the impeller shaft can rotate smoothly. This is the #1 cause of premature pump failures on the Red Dragon (Not the RD3) pumps. Once the bearing is cleaned, refer to your instruction manual for how to get the bearing back in. In needs to be seated properly and the o-ring that holds it in place needs to seat into the bearing cavity properly. Also check the end of the impeller shaft to make sure it's clean and smooth as well. If you pull the impeller out of the block and the bearing is stuck to the end of the shaft, you aren't doing your mainenance properly and you may have killed your block as a result. With the bearing stuck to the shaft, the impeller will not spin and the pump will go into protection mode. Any friction between the bearing and the shaft creates excessive loads on the pump motor that can lead to overheating and premature failure so please take care of your pumps!!!

Typical salt creep in the Venturi port and the #1 cause of inadvertent skimmer overflows in any skimmer!

A closeup of the salt creep!

What a nice clean Venturi port should look like.

All disassembled after a thorough cleaning. Note the tools I use for cleaning. Scrub brush, tooth brush, skewer. The vinegar was camera shy!

All back together. Note how clean this pump looks. You would never know it was 1.5 years old. It looks like new inside and out! Yours should too!

Director Customer Support Royal Exclusiv USA
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Last edited by slief; 10/06/2017 at 11:57 AM.
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