Air coming in?

Long time since I've been here but that's (mostly) because I've had no issues for years.

Now all of a sudden I'm getting a tremendous amount of air in the system, so much that the pump doesn't work correctly (and the filter never quite fills), so I go ahead and shut everything down, clean the filter, make sure there is no obstruction to any of the intakes but with no luck.

I'm no expert but it seems to me this is pretty obviously a closed system, so I'm guessing that ruling out some sort of freaky obstruction this has to be a pump propeller (or whatever the heck it's called) issue, right? Or is there something else I could check for?

TIA for any assistance.

Maybe an impeller issue but are you getting water flow?
Easiest parts to check and the most likely candidate is the pump pre filter lid gasket/seal.
It's a leak on the inlet side so maybe a crack in the skimmer or broken pipe connection but pre filter is right where I wood start. I have had customers tell me it isn't the pre filter as they had checked it, only 5 minutes later to be proved wrong.

The basket was the first place I checked (and where I could see the water gushing in but never quite filling it up completely). While I can't be sure I *think* it's just the pump going bad. After I cleaned the filter (and checked the skimmer to see if it was clogged) and then restarted I *finally* got full water flow -- but the pump now seems to be making a terrible, awful noise (if it was a car I'd think bad bearings).

I hate to think about replacement but it's probably due (about five years). This will be the first time I've ever replaced a pump myself so it will be an adventure (the last time I ended up paying about $500 in labor and said "Never again").

OK so it does now sound like a pump issue, could something have gotten into the impeller? I have had to fetch out all manner of stuff from impellers and that would at least not require a full strip down, just removal of the front cover if you can't get your fingers down inside to fish anything out. (totally unplug the pump first).
Failing that it could well be the bearings, if you are not up to the job it's worth finding a shop who can, bearings are low cost and reasonably easy to change providing the bearing hosing isn't damaged through running excessively hot.
Good luck and let us know how you get on.

Hmmm, it defintely *could* be something in the impeller. Right before this happened there was a ton of crap I vaccumed out and a lot of it ended up in the catch basket, so it's always possible something slipped through into the pump itself. But when you say "removal of the front cover" what do you mean by that? I thought the pump/basket/impeller were all of one piece.

I'll go out and take a look today (and see if there are any internet videos showing me what you are talking about). The good news is the last pump they put in was done with screw settings on both of the intake and output pipes, so changing the pump isn't going to require any cutting (at least in terms of taking it out -- I may have to cut to fashion some fittings on the new one to fit this setup).

The majority of pumps separate to facilitate cleaning leaving the back plate and impeller attached but allowing you to remove the front of the pump and pre filter "the wet end" What pump do you have?

Here's images of my pump (the Pentair Sta-Rite P6RA6F-206L Max-E-Pro). I took off the motor part and AFAIK the impeller was clean (I can't physically move anything on either side of this assembly).

I'm hoping the pump has just gone bad, as I ordered another one (the same kind) which should be relatively easy to replace (obviously I could easily just put the pump part back in, but I most likely will swap out the whole pre-filter and housing, as it appears to be a simple screw set up that, at the most, will only require me to make some fittings at the pump side, which is pre-threaded on both connectors).

https://dl.dropboxusercontent.com/u/44162406/Pump01.jpg
https://dl.dropboxusercontent.com/u/44162406/Pump02.jpg
https://dl.dropboxusercontent.com/u/44162406/Pump03.jpg