Mystery leak from underneath Pentair SuperFlo 340038 pump - any ideas?

[just4747]

Hi all! We recently bought a house with an in-ground pool. The pool was installed in 2014. The current Pentair SuperFlo 340038 pump has a 2017 manufacturing date on the motor part (I think) and a 2013 date on the pump part (again, I think). See labels below:



Anyway, a couple weeks now after having the pool opened and operating the filter frequently on a daily basis, I have noticed what looks like a slow, subtle leak from the bottom of the pump on the pump side (underneath the top viewport cover area). I looked closely and nothing obvious can be seen as the origin of the leak - it is kind of just seamlessly seeping from the bottom of the pump and onto the concrete base. It's not the two drain/pressure plugs, not any of the piping connections/fittings, not from the top viewport cover. I have to get down really low to see that the wetness is coming from directly underneath the round part of the pump itself on the far end, but again, I can't see any obvious source or place where the leak starts from. Please see pics below showing it as best as I can (ignore the dirty water in the pump and the wetness on it in the very last zoomed out pic, that one is from before the filter was cleaned).

Is there a known thing in this area that could be leaking on a pump of this age? I can't really get a better look without shutting everything down, draining, and disconnecting the pump which I don't want to do until I have to. If this might be something repairable, I am handy and would attempt it. The system seems to be running fine right now, the pump has stayed full so far, but I assume this slow leak will eventually cause issues with pressure or the pump being filled, or get worse (or both).

ANY help or suggestions at all would be appreciated. Thanks!

 

[just4747]

Bump, anyone have any thoughts? I really want to look into this before it becomes an issue if possible. Thanks in advance!

 

[Texas Splash]

Could be the motor shaft seal. A quick Google or YouTube search and you'll see what I mean. The shaft seal can develop a slow leak and that dripping will flow into the motor housing and find a place to escape. Over time it can result in corrosion. It may be time to order a new seal kit (Go-Kit) for that pump/motor and simply change the shaft seal, seal plate gasket, etc all at one time.

 

[just4747]

Could be the motor shaft seal. A quick Google or YouTube search and you'll see what I mean. The shaft seal can develop a slow leak and that dripping will flow into the motor housing and find a place to escape. Over time it can result in corrosion. It may be time to order a new seal kit (Go-Kit) for that pump/motor and simply change the shaft seal, seal plate gasket, etc all at one time.

Thanks for that info, will be looking into that.

Just for planning - to remove and disconnect the pump in order to get a better look and work on it, what's required? Just powering down the system/unplug pump, closing off the inlet line valve going to the pump, draining what is in the pump (via the two small drain plugs I assume?), then just unscrew both large pipe/fittings and remove entire pump? One issue I see is that I can't just disconnect the halves of the pump because the whole pump is solidly in place due to the pipes connected to it, and one is going into the ground and one to the pump, so neither moveable - looks like it might be tricky to just get the pump itself out of there to do anything to it.

What about the filter side of the pump/inlet side? Do I need to drain the filter or do anything special first or not really? Just want to make sure I close off/remove any water where necessary before unscrewing anything.

Also, the guy in this vid mentions just the pump seal itself which I assume is between the two halves - is that the same thing as the motor shaft seal?:

Thanks.

 

[Texas Splash]

Just powering down the system/unplug pump, closing off the inlet line valve going to the pump, draining what is in the pump (via the two small drain plugs I assume?), then just unscrew both large pipe/fittings and remove entire pump?

That's about it. System off. Pump circuit breaker off. Close any 3-way valves on the pad first so water doesn't keep flowing. You might need to drain the filter a bit. You'll know if you remove the pump clear lid first (after closing all the pad valves) to allow water to settle before separating the pump pot from the motor end.

 

[just4747]

That's about it. System off. Pump circuit breaker off. Close any 3-way valves on the pad first so water doesn't keep flowing. You might need to drain the filter a bit. You'll know if you remove the pump clear lid first (after closing all the pad valves) to allow water to settle before separating the pump pot from the motor end.

Thanks. I edited my post so you probably missed it, but is this essentially what you are talking about? Is this seal the same thing as the motor shaft seal?:

 

[Texas Splash]

Correct. You have the large seal plate gasket, but then you also have the small 2-part ceramic motor shaft seals.

 

[just4747]

Correct. You have the large seal plate gasket, but then you also have the small 2-part ceramic motor shaft seals.

Great thanks again!