• Dart pump wailing - replacing seals and bearings

    My reef uses two Dart pumps. One is used as a return pump, the other as a means to feed all equipment with a manifold of valves. The return pump started making noise about a week before I had to fly to MACNA 2011. Swapping the noisy pump out with my back up Dart pump wasn't an option; that one leaked at the seal so the noisy one was re-installed.




    In the past six weeks, the noise level had only gotten worse and worse. Buying a new pump was the obvious solution, but this one was only used for 8 months, and my funds were spent elsewhere. My friend Bobby told me we could replace the bearings and correct the problem. He had me order bearings found on Ebay. I found a package of 10 for $11.50 with free shipping, sold for skateboarders.



    Within a week, the bearings arrived. I also had a new seal at the ready.



    The pump was easily removed from the plumbing by unscrewing the union valves.



    The first thing to remove is the impeller housing. There are six nuts that need to be removed to pull off the cover.




    With the cover out of the way, the impeller is visible.



    Not pictured is how the cooling fan cover at the end of the pump was removed. Next, a flat-head screwdriver was then inserted into the slot of the drive shaft to lock it in place, allowing the impeller to be unscrewed and set aside.




    The other half of the impeller housing is held onto the motor with four screws. Note the four keyhole slots in the picture below. Once the screws have been carefully loosened, the black section can be twisted slightly and separated from the pump's motor section. Note how the seal has begun to display signs of rust and damage. It was leaking slightly.





    The motor's threaded driveshaft needed to be cleaned up slightly. You can see three of the four screws that held the black shroud in place, and the grey impeller in the background.



    The next part that has to be removed is the cast metal section. It is held by three points where the metal has been dimpled inward. Using a screwdriver, Bobby pried the metal outward enough to release its hold. One spot is already done right above his thumb in the next picture. The next one is facing me in this picture.



    With the metal piece carefully pulled out and set aside, this core driveshaft was pulled out. The bearings are what are about to be replaced.



    Using the bearing-pulling tool, it was easy to remove the first one. This tool can be purchased cheaply at Harbor Freight, as the bearing isn't nearly as secure as it might be in other applications. It just pulls it off gradually as you turn the handle.



    The new bearing was slid down the shaft and a deep socket was used to press the bearing downwards with each tap of the hammer.



    The other bearing was a little difficult to reach with this tool, but even with only two hooks of the three grasping it, the old part was removed.



    This little retaining ring/clip is what the near bearing has to slide up against.



    The new bearing is installed.



    The drive shaft assembly was installed in the same orientation it came out. Please remember to install the two spring clips at each end prior to installing the cover plate. It helps keep the drive shaft centered within the housing.

    Using a screwdriver and hammer, the three dimples were hammered back down to snugly hold the metal place in place as before. This picture shows it prior to being bent, and the next image as it should be.






    Now that the motor was repaired, we changed out the seals. The seal came out easily with a screwdriver, pressing against the rubber liner and prying upward.



    The new one was pressed in by hand.




    The other half was depicted near the top of this article. Here's the housing with it removed. Some of the gasket sealer material was still present, but not anything to be concerned about. I wiped it away with a paper towel.





    Using some aquarium-safe silicone, it was applied to the metal perimeter of the seal. This silicone is sold at Home Depot near the tape and glue section.







    And was pressed into the black housing by hand.



    With this task done, the impellar housing's back plate was aligned with the motor's four screws. These were inserted into the four keyhole slots, and the black section was then twisted to lock it in place.



    Using pliers, the four screws were snugged down to hold the plate in place. It doesn't have to be tightened excessively.



    Done.



    The impeller was screwed back onto the threaded end while a screwdriver at the opposite end prevented the drive shaft from spinning.





    The old bearings and seals.





    The large O-ring inside the cover was positioned in place, smearing the silicone grease over it evenly and the cover plate was then reattached. The bolts and nuts were inserted and tightened down. Done.



    The pump was installed, the valves opened up and then turned on. It is much more quiet, nearly perfect. The question remains if these bearings designed for skateboarding are going to be good enough quality for long term use or if a different source will be needed.



    I hope this article helps. I can't omit the fact that the people at Reeflo Pumps offer excellent customer support and can help resolve issues. If you are a handy person and want to tackle this yourself, now you know more. If you don't want to commit to this level of repair, contact Reeflo directly. I still plan to buy one more pump to have at the ready for when one fails, but being able to fix one locally and not have to wait for it to be shipped, repaired and shipped back is why I proceeded accordingly. Plus Bobby said it was easy.

    Additional links:
    How to replace the seals on a Dart Pump: http://www.melevsreef.com/dart_seals.html
    Reeflo Pumps: http://www.reeflopumps.com/
    Comments 16 Comments
    1. dahenley's Avatar
      dahenley -
      bearings can be used for skate's (boards) and are fine for pumps, as long as they are high speed bearings. t he same bearing can be found at sporting good places but they are low speed. (been there.... used them and non-high speed bearings are noisy when you put them on pumps. ) since yours isnt noisy, it should be fine. (mine was noisy within seconds of using a non high speed bearing) good write up! it will be used!!
    1. OneReef's Avatar
      OneReef -
      I wonder if rust seeped into your tank, and if it would have been enough to hurt anything.......
    1. melev's Avatar
      melev -
      It wasn't much of any rust in the water, and when you consider that people use rust (GFO) to get rid of phosphates, that little bit over that one month duration isn't enough to be of concern.
    1. DJ in WV's Avatar
      DJ in WV -
      I am definitely not a fan of reeflo seals. If those darts had the baldor motors you wouldnt have had to be replacing bearings
    1. Bobbywade's Avatar
      Bobbywade -
      Baldor motors use the same bearings in them same brand and the front bearing is the same number! When you get salt water into the bearings any motor bearing will rust out doesnt matter brand. Baldor motors are cheap I replace them all the time just bigger scale 200HP+

      Quote Originally Posted by DJ in WV View Post
      I am definitely not a fan of reeflo seals. If those darts had the baldor motors you wouldnt have had to be replacing bearings
    1. Bobbywade's Avatar
      Bobbywade -
      The reason for the seal to go out is that the spring and inner skirt seal clips are not stainless and when they run in saltwater 24/7 then they rust out and give way to a leak. The reason for his leak we took out the impeller to use for another pump and moved the seal and caused it to leak. We waited to change it when the bearings came in.
    1. DJ in WV's Avatar
      DJ in WV -
      Im on the 3rd seal in mine and its only been running since feb 2011. It make micro bubbles know matter what I do with it, sounds like a ventura driven skimmer if I let it run wide open without valving back the output. I noticed it looked like the impeller is coming apart last seal I put in. You can see cracks where the blades meet the front and back plate Not sure if this is causing the bubbles and noise or not. Maybe I just got a lemon but it have left a sour taste in my mouth. Id take a baldor to most of the other junk on the market today. The only motors I have that have been in use longer are westinghouse but with anything today im sure they are not build as well as the old ones I have tho the one on my pump seems to be fairly robust. If you go hunting bearing again check for a distributor of timken bearings they hold up well and I believe are still manufactured in the us
    1. melev's Avatar
      melev -
      Have you contacted Reeflo about your pump, DJ? It may be under warranty.
    1. DJ in WV's Avatar
      DJ in WV -
      Yea Marc they sent me the first new seal I bought the second, but said the warranty had been dead for 3 years when I bought it. I bought new in feb from reefspecialtys . They said it had been in inventory there for awhile but the warranty should have started when I bought it not by the manufacturing date. I need to get back ahold of them and try to get it resolved. I will say tho Beth at reeflo was polite about everything and did send the 1st seal out and no cost even tho she said the pump was not under warranty
    1. chuck's Avatar
      chuck -
      DJ Timken bearings are still made in the USA. Timken is one of my mills we buy from.
    1. DJ in WV's Avatar
      DJ in WV -
      Dont mean to hijack Marc thread But contacted reeflo today and they are sending me out the new impeller at nc to try to resolve the issue, warranty wasnt even question this round so +1 on the customer service and hope this fixes the problem Ill have my son help make a short vid of the the noise before disassemble and of the impeller so may it might help someone else in the future
    1. melev's Avatar
      melev -
      That's good news, DJ.
    1. dahenley's Avatar
      dahenley -
      DJ: make sure you silicone the bushing good. and dont put silicone grease on the 2 mating surfaces of the seal. also, try not to put finger prints on the seal either. (the oil from your finger prints will effect it too) once you put the seal and impeller on, you can run the pump out of water and see if the impeller wabbles (where the 2 seals meet) if all good, then silicone grease your o-ring and put the housing back together MARC: you should re-build your back up pump, but leave your impeller housing off. that way when you re-place the pump during survice, all you have to do is swap over the front housing and it already has the fittings set and leak free. (just a suggestion)
    1. melev's Avatar
      melev -
      Just a follow up. It's been about two months since the replacement bearings were installed, and they are working out well. Very quiet, and the pump is running well.
    1. ProVega350's Avatar
      ProVega350 -
      Melev,

      Thanks for the great article. I don't see where you got the seals from or how much you had to pay for them. Would you post up this additional information?

      Thanks,
      Leo
    1. melev's Avatar
      melev -
      The seals were purchased from Reeflo directly, the vendor of these pumps. A set of seals are $20.