View Full Version : Sequence DART seal failure in 18 months?

04/10/2006, 09:44 AM
Yesterday, my Dart would not restart after I fed my tank. It just sat there humming. The pump had been running for 18 months without a problem. Until now.

I noticed a strange buildup of a reddish-grey crunchy dust near the base of the impeller housing where the mounting holes are. It appeared to be coming out of the seal area. Upon closer examination it looked like decomposing metal chunks mixed with dried salt and houshold dust. So I opened the pump. The threaded shaft of the impeller had two cracks in it where it screws onto the drive shaft. I tried to remove the impeller and holy crap it wouldn't budge! It finally gave and I was able to remove it. The threaded drive shaft was all corroded. All the metal parts of the seal were rusting and decomposing. The seal fell apart in my hands, the spring split into two peices. I've got pictures on my camera. I'll post them later.

I am questioning if the seal that was installed in my pump was actually saltwater safe? I don't think after two years there should be this sort of metal decomposition on a saltwater seal.

Fortunately I had ordered a spare seal months ago. I had no idea I would need to use it so soon. I would like to hear if anyone else has had similar problems with these pumps.

BTW what happened to the MDM Sequence Forum?

04/10/2006, 10:51 AM
You might just try calling MDM

04/10/2006, 11:21 AM
I will be contacting them soon. I'll be sending them the pictures. I just wanted to know what other peoples experiences have been with these pumps.

04/10/2006, 11:52 AM
I've never had any problems with any Dart I have ever owned.

04/10/2006, 01:12 PM
the seals will go bad in a hurry if the dart is sucking air. BTW, what type of housing does you impeller have? is it clear, blue or black?

04/10/2006, 01:15 PM
It's never sucked air. Only to prime the air pocket in the closed loop and that only lasts a few seconds until the pipes are primed and the bubbles dissipate. Mine has the clear blue housing.

One thing I forgot to mention, when I took the impeller housing off, the four screws that attach it to the motor face were all loose. They were never tightend at the factory or worked loose over the 18 months the pump was running.

04/11/2006, 08:15 AM
Here's the pictures of the damaged seal and other parts:

Here is the seal. Destroyed after only 18 months of service. The spring actually has a hole down the center where is broke into two parts.

This is the impeller thread. There was so much corrosion inside the threads that it split open upon removal.

The shaft was much worse. I had cleaned off most of the corrosion with my Dremel before I realized I should be taking pictures of it.

I'm forwarding all this to MDM Sequence. It's still under warranty.

04/11/2006, 11:51 AM
MDM responded very quickly to my email. They had no explanation for the seal failure but I am happy to say they are sending me a new seal to replace my spare that I had to use, a new impeller and the more robust black motor bracket to go with the stronger black impeller housing. That's great customer service! Cudos to MDM Sequence!

04/13/2006, 02:25 PM
I have always been impressed with MDMs customer service. :)

08/28/2006, 11:11 PM
Exact same problem over here:






I hope I get as good a response as u did. :(

09/07/2006, 07:39 PM
Guys whats MDM's E-mail. I have the same problem after 12 months:(










09/07/2006, 08:36 PM
They sent me a new pump within a day of contacting them.

Here is the website:http://www.mdminc.com/Reeflo.htm

09/08/2006, 09:56 AM
We do not know what has caused your seals to become rusty. It is NOT a common problem. these seals are saltwater ready, however, the individual seals could have some weaknesses, unfortunately there is no way to test to see if seals will go bad after a year....so we'll continue to address the problem with customer service.

09/08/2006, 10:29 AM
Which is excellent by the way.

09/08/2006, 12:33 PM
I talked to Beth at MDM she took care of the problem and will be sending out a refurb. She was great to work with.. She knows her stuff.

I also got 6 months added to my warrenty:)

09/08/2006, 07:30 PM
Ya, customer service is top notch.

09/09/2006, 08:38 AM
I hope they figure out why the seals are failing. I can't keep replacing them every year. What a PITA!

09/09/2006, 09:06 AM
THis is the first time ive heard of it happening so i dont think its too common.

09/09/2006, 06:02 PM
Well in a few days I will be installing my second new seal. That's three seals in two years.

09/09/2006, 07:02 PM

09/09/2006, 07:30 PM
This same thing happened to my friend. His seals went within 3 months and the next 2 sets still had salt creep coming out of them.


But I will give it to the customer service, they sent him some asap without any question. And a new pump just in case.