Leaking after motor and shaft seal replacements: Replacing seal plate?

chulinet

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May 8, 2020
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Sugar Land, TX
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Hello All,

After replacing the motor for my WhisperFlo WF-28 pump and all related gaskets and the shaft seal, I noticed a steady stream leaking from the bottom of the seal plate (see attachments). It turned out two small pieces cracked off the seal plate, and it might have happened when I tried to take off the old and the new seal part from it.

Is it time for a new seal plate or some sealant/lubricant can fix it? I used Magic Lube when I replaced the seal, and it does not seem to prevent the leaking image4.jpegLeakingStream.pngInkedimage0_LI.jpgsealPlate.png image0 (1).jpegat all.

Thanks in advance!
 
Did you coat the seal’s outside surface with silicone sealant (RTV) before installing the new seal? You’re supposed to apply a thin coating of silicone sealant prior to installing the seal, and then you need to let the silicon cure for several hours before putting water back in the pump.

It sounds like you may have missed the sealant step? Those chips in the seal plate can be covered with sealant and they will probably be fine.
 
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Thanks for the reply.

I did apply Magic Lube #631, yet I might not wait for several hours before trying out my new motor. Is magic lube fine for this purpose? I will wait and see how long it cures before putting the motor back to the pump.

Thanks again!
 
I'd say I've never heard of using rtv there and would say it's time for a new seal plate but can't hurt to try and maybe get lucky but remember it's a bandaid at most and can take out the motor if the water goes down the shaft.
 
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Here’s a video from Pentair that shows how to replace the seal in a Whisperflo pump. They state that the seal’s outside metal surface should be coated with silicone sealant before pressing it into the seal plate.


From what I can see online MagicLube 631 looks to be a Teflon lubricant rather than a sealant. I’m not sure it ever dries hard but I’ve never used it and I could be wrong about it.
 
Thank you MSchutzer and wireform. I am having a difficult time to find a matching seal plate for my WhisperFlo WF-28 pump. I might have to get a seemingly compatible one if the silicone sealant does not stop the leaking.

It seems that the leaking through the flange of the seal is on the outer side of the seal plate, and the shaft should not get affected by it. Right?

Magic Lube #631 does not seem to dry hard, despite this claim:
5 oz. Tube of Silicone based Sealant/ Lubricant. A PTFE based Multipurpose Sealant/Lubricant. Can be used in both wet and Dry Environments.
 
The chips in the seal plate are up near the lip of the seal. The walls look okay and I would think it will be fine as long as you put some silicon sealant in there before you press the seal in. Just make sure everything is dry and clean before you apply the sealant. You may want to clean the seal plate area with some isopropyl alcohol to remove any grease, from the previous installation attempt. And give the silicon plenty of time to dry before adding water back in the pump.
 
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Update: Still leaking.

Since I could not find The Silicone 2.8 oz Clear Aquarium Sealant by DAP in any local stores, I used Loctite clear silicone instead. While trying to push the seal into the seal seat, I found out that the flange of the seal part on the seal plate is a little too wide for it to be completely seated. That might be the root cause of the leaking.

I bought the seal from eBay [[KIT77] Fits Pentair WhisperFlo Swimming Pool Pump Parts Seal Gasket O-rings | eBay]. It came in a transparent plastic bag with handwritten PS-1000, instead of a box. Is it possible that the seal has defect? Anybody has similar experience with it?

Thanks,
 

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Every seal that I have replaced has come in a genuine US Seal box. You want a PS-1000 seal, or better yet the PS-3865 (same size seal) upgraded for salt water pool service. It’s only a few bucks more and I would go with the PS-3865. Make sure it’s a genuine US seal.

With the proper seal the lip will fit in the cutout on the seal plate, and when pressed in place it will be flush with the surface of the seal plate.
 
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Sorry, I accidentally hit send before finishing the message. I edited the message and finished it. You’re correct, you want a PS-1000 or better yet the PS-3865, also called PS-3865R which is better quality for salt water pools.

Again, Sorry for the confusion.
 
Thanks you so much, MSchutzer. Appreciate your help!

I will go get a genuine PS-1000 or PS-3865 instead. The current one is visually tilted on the seal plate, no matter how hard I pressed it.
 
Update: Still leaking.

Since I could not find The Silicone 2.8 oz Clear Aquarium Sealant by DAP in any local stores, I used Loctite clear silicone instead. While trying to push the seal into the seal seat, I found out that the flange of the seal part on the seal plate is a little too wide for it to be completely seated. That might be the root cause of the leaking.

I bought the seal from eBay [[KIT77] Fits Pentair WhisperFlo Swimming Pool Pump Parts Seal Gasket O-rings | eBay]. It came in a transparent plastic bag with handwritten PS-1000, instead of a box. Is it possible that the seal has defect? Anybody has similar experience with it?

Thanks,
There are many junk clones in pool supply channels. I've seen several videos and articles by "pool professionals" that recommend U.S. Seal products as the most reliable. Also that the ceramic of the new seal should never be touched. Hands transfer acids that ruin the surface. Magic Lube is not a sealant.
 
Thank you generessler. I learned it the hard way! My pool is green, and I am so experienced at taking out the shaft seal now:) The one I bought from eBay this month already looks torn to me, although I am not 100% sure if the leaking is caused by it.

There are many PS-1000/PS-3865 at Amazon and Inyopools, with different prices. How to tell which one is more reliable?

Thanks!
 

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C.J., one other thought. In addition to the two halves of the seal there is a rubber washer that goes on the impeller screw. I assume you replaced this washer with the new one from your go kit? If this washer was left out that could also cause leaking around the motor shaft.
 
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Thank you generessler. I learned it the hard way! My pool is green, and I am so experienced at taking out the shaft seal now:) The one I bought from eBay this month already looks torn to me, although I am not 100% sure if the leaking is caused by it.

There are many PS-1000/PS-3865 at Amazon and Inyopools, with different prices. How to tell which one is more reliable?

Thanks!
I ordered Amazon.com: US Seal Manufacturing PS1000 Seal Assembly: Garden & Outdoor . I guess it could still be a fake, but the packaging looked legit.
 

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