Silicone sealant under lip of new shaft seal?

CajunGuy

Well-known member
Apr 6, 2016
304
Louisiana
#1
Maybe I'm over thinking this...but from everything I've researched, this seems like a 50/50 opinion type of thing. What's you guys opinions? To me it seems like the sealant would be beneficial because it will prolong water from getting under the lip and behind the seal. Just need to be careful not to get any on the face of the seal.
 

CJadamec

TFP Expert
Apr 29, 2016
2,194
Quaker Hill, CT
#2
Where is the fifty fifty opinion coming from? What sources did you find that sealant is a good thing for a shaft seal. The lip seal on the shaft is designed to be able to move on the shaft. As soon as the seal moved, and it will, the sealant will no longer seal the lip seal.
 

CajunGuy

Well-known member
Apr 6, 2016
304
Louisiana
#3
Where is the fifty fifty opinion coming from? What sources did you find that sealant is a good thing for a shaft seal. The lip seal on the shaft is designed to be able to move on the shaft. As soon as the seal moved, and it will, the sealant will no longer seal the lip seal.
Maybe I'm confused, but the shaft on my WhisperFlo motor slides right through the spring side of the seal that is seated in the middle of the seal plate. Are you telling me that both sides of the seal spin once the pump is turned on? When looking at my setup, it seems like the spring side lodges on the seal plate and wouldn't move, only the shaft would spin inside it. Again, not really sure how it works, I thought only the white ceramic side seated in the impeller spun.

Read this thread Step 8 Pentair Whisperflow seal replacement How-to (w/ photos))
 

CJadamec

TFP Expert
Apr 29, 2016
2,194
Quaker Hill, CT
#4
Ceramic spins. Carbon doesn't spin. Carbon on the shaft is spring loaded and will move slightly as the shaft floats on its bearings and undergoes thermal expansion. It's not the seal moving so much as the shaft moving realative to the seal. At best silicone will do nothing at worst it will cause the seal to leak or fail premature.
 

CajunGuy

Well-known member
Apr 6, 2016
304
Louisiana
#5
Ceramic spins. Carbon doesn't spin. Carbon on the shaft is spring loaded and will move slightly as the shaft floats on its bearings and undergoes thermal expansion. It's not the seal moving so much as the shaft moving realative to the seal. At best silicone will do nothing at worst it will cause the seal to leak or fail premature.
Thanks for great explanation man! I'll leave it off!