Pool pump and impeller question...thoughts?

Absolutely no lubrication should be put onto a mechanical shaft seal. Not even onto the rubber cup for the ceramic piece or the rubber that is on the shaft. The face where the ceramic (white disk) and carbon (black disk) should be kept as clean as possible. You shouldn't even touch them with bare fingers if you can help it.

The bad seal could cause the motor to not spin well. When you put the impeller on it compresses the spring in the seal pushing the carbon and ceramic together. Normally those faces spin against each other and the carbon face will slowly wear away until the seal fails. Which under normal operation will take a very very long time. Things like running the pump dry, cavitation from suction air leaks, and overheating the pump will drastically reduce the life of a seal.
What about the rust on the shaft near the thread end where the impeller screws on? Should I remove this rust with some light sand paper?

So no lube on shaft seal...got it. But the seal plate gasket and diffuser gasket should have a light coat of lubricant correct?

Could all this (bad shaft seals, cracked grommet housings, bad seal plate fit) have also caused air to get into my pump basket? Reason I'm asking is because I've noticed (ever since we bought the house a year ago) that I've always had a more air in the top of my pool pump basket than my spa pump basket and often I would get air bubbles (sputtering) coming from the pool return jets at times.
 
You can lightly sand the shaft where the rust is. The best thing to use is scotch bright pads or fine plumbers cloth. Sand the whole shaft in the rusted area as evenly as possible.

The seal plate and diffuser O-rings should be lubricated with o-ring lubricant ( or 100% silicone grease). Same grease that you should be putting on the basket cover o-ring from time to time.

The problems with the pump could be the cause of you air issues its hard to tell though. Deal with the known bad pump first and evaluate the plumbing after.
 
CJ, thanks for the help! As of now, I'm leaning towards just replacing the seal plate and shaft seal and try to get another Summer or two out of this setup (and motor) to save some money. My pump volute appears to be fine from a visual inspection although I need to check the grommets on the pump volute too. If they are not cracked and in place then I think I should be fine with just replacing the seal plate and shaft seal for now.

When the motor goes bad, I'll probably go with a dual or VS pump that is more energy efficient.
 
I went ahead and bought this http://www.amazon.com/Pentair-35020...=1492532054&sr=8-1&keywords=seal+plate+350202 OEM Pentair seal plate kit (350202) that included the shaft seal (already installed on seal plate side) and gasket seal along with the seal plate for $71. I'll pickup the o-ring for the diffuser at my local pool shop. I'll cleanup or replace the 4 bolts that attach the motor to the seal plate. I have some silicone lube (Super Lube) already.

This should be everything I need right?

P.S. Once I get the all the new items installed and screw the impeller back on, there should be no rubbing and it should spin pretty easy on the shaft right?
 
That's enough parts to tackle the seal plate by the looks of it. I would look closely at the diffuser and impeller for any signs of wear. In particular the center of the impeller where it sticks into the diffuser. Any wear in that area cant impact pump performance.
 
That's enough parts to tackle the seal plate by the looks of it. I would look closely at the diffuser and impeller for any signs of wear. In particular the center of the impeller where it sticks into the diffuser. Any wear in that area cant impact pump performance.
Do you think it would be a good idea to maybe bring the impeller to my local pool store and compare it to a new one to see if it is good enough to reuse?
 
A water based o-ring lubricant might be ok on the rubber parts of the seal. I was always taught it was best practice to keep lubricant away from mechanical seals if at all possible. Some seals are more tolerant to surface contamination some aren't it all depends on their design and contact pressure between the faces. In general any type of oil or grease contamination on the seal can cause them to fail right off the bat or have a shortened service life.
 
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Ok after looking at the parts diagram for the Whisperflo pump, I have another question. It shows that there should be a rubber washer (075713) that the set screw goes in when screwing it in counter-clockwise? Look at mine, it doesn't appear that it's there, unless it's been worn down. Does mine look like it's missing? It would be #15 on the diagram. Unless the rubber washer fits inside there and the screw flange is just covering it up?
 
A water based o-ring lubricant might be ok on the rubber parts of the seal. I was always taught it was best practice to keep lubricant away from mechanical seals if at all possible. Some seals are more tolerant to surface contamination some aren't it all depends on their design and contact pressure between the faces. In general any type of oil or grease contamination on the seal can cause them to fail right off the bat or have a shortened service life.
Yup