New pool owner, can I do this?

Rats. I was a afraid of that but glad you were able to confirm. That eliminates a LOT. That only leaves:
- Pump basket O-ring (already checked)
- Pump drain plugs (already checked)
- Required time for the pump to pull water up and through the pipe itself (assuming you've left that on long enough)

Weird that at one point you mentioned the water would disappear from the basket, but perhaps that's all the suction that pump had left in it. Stand-by.
 
Yes several times I have left the pump running 2-3 minutes with the same reults.

And yes, every time I fill the strainer basket with water and turn the pump on, it immediately and quickly pulls the majority of that water into the filter lines and nothing else enters the basket. Then when I shut the pump off, the majority of that water steadily flows back into the basket.

Pentair pump/motor info:
Pump model # 34-0037
Serial # 1/29/D08, self priming, 3/4 HP, 1.30 SF, .90 SFHP

Pentair motor model number # 186236-20, RPM 3450
 
Yes several times I have left the pump running 2-3 minutes with the same reults.

And yes, every time I fill the strainer basket with water and turn the pump on, it immediately and quickly pulls the majority of that water into the filter lines and nothing else enters the basket. Then when I shut the pump off, the majority of that water steadily flows back into the basket.

Pentair pump/motor info:
Pump model # 34-0037
Serial # 1/29/D08, self priming, 3/4 HP, 1.30 SF, .90 SFHP

Pentair motor model number # 186236-20, RPM 3450

Given all that you have tried, this is the only thing I can think of.

When priming, normally, the pump should start to draw water from the pump basket but then it should return that same water through a small slit in the bottom of the volute. Since you are only seeing water leave the pump basket and there is no churning (i.e. recycling), I suspect that slit could be blocked with debris and it is preventing the re-circulation from occurring and without that, the pump cannot build up enough suction to force the water to flow into the basket. When you turnoff the pump, the water just flows back through the impeller.
 
The only way to clear it would be to take the pump apart. You can also inspect the impeller and make sure that is completely clear at the same time.
 

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Not that hard really. Just remove the four large bolts on the housing and it separates in two pieces.
 
Ok. I've found some stuff online that should help but I'm not clear about one thing, do I need to completely unhook the electrical wiring running into it in order to do this or can that be left alone? (turning off the breaker obviously)
 
Have you tried disconnecting the 'out' from the pump? and seeing if you get any suction?
Maybe your filter or something downstream is so clogged up there is no path out for the water

If there is a blockage after the pump then if it cant blow it cant suck...

You might get wet :)
 
Have you tried disconnecting the 'out' from the pump? and seeing if you get any suction?
Maybe your filter or something downstream is so clogged up there is no path out for the water

If there is a blockage after the pump then if it cant blow it cant suck...

You might get wet :)

I'm sorry, not sure what you mean by the "out" .... I have disconnected both the skimmer and main drain lines, connected a PVC pipe and ran that straight into the pool and still got no suction. In a separate test I also was able to send water manually with a hose from the pump back to the pool thru my sk/md lines, so I do not think I have a clog in those lines.

- - - Updated - - -

Just turn off the breaker and you should be fine.

Mark, last question on this before I take the pump apart later today. Is there any chance that I have an air leak on the suction side somewhere? I did check my o-ring and then ran some smoke around the connections and valves, did not notice any smoke being pulled in anywhere but I know that was not exactly a comprehensive air leak test. Could a leak cause what I'm experiencing?
 
What dibbler means is to disconnect the pipe between the pump and the filter and turn on the pump to test a theory that a completely stopped up filter or pressure side plumbing would stop the pump from priming.

Yes, a suction side air leak could prevent a pump from priming. But, didn't you already bypass the suction side plumbing to eliminate that?
 
I think what Dibbler meant was the discharge or return side of the pump. But that doesn't come into play until priming has actually started (i.e. water is flowing) so I don't think it is the discharge side of the pump.

And yes, it could be an air leak but the description you gave about the water in the pump basket made me think that perhaps it could be the water return in the volute that was plugged. The only way to test for a leak in the lines is to perform a pressure test. That is a lot more involved than taking apart the pump so to me, that should be done first to rule it out.
 
Your temp line to from the pump to the water should've ruled-out any possibility of a suction leak other than on the pump strainer basket itself. My hope is that once you pull those 4 bolts off and slide that motor backwards you find a wadded-up bunch of junk stuck behind the wet-end from your first start after winter. Some easy spring cleaning so you can get back to business. Best of luck! We'll be watching for your update.

- - - Updated - - -

Oh and hey .... did we ever ask or discuss this ...... in your pump strainer basket, do you have a removable leaf basket in there? Designed to catch most stuff before making its way to the pump? I couldn't remember if we talked about that.
 
Your temp line to from the pump to the water should've ruled-out any possibility of a suction leak other than on the pump strainer basket itself. My hope is that once you pull those 4 bolts off and slide that motor backwards you find a wadded-up bunch of junk stuck behind the wet-end from your first start after winter. Some easy spring cleaning so you can get back to business. Best of luck! We'll be watching for your update.

- - - Updated - - -

Oh and hey .... did we ever ask or discuss this ...... in your pump strainer basket, do you have a removable leaf basket in there? Designed to catch most stuff before making its way to the pump? I couldn't remember if we talked about that.

Yes my strainer DOES have a removable basket. Before I even turned the pump on the first time, I removed that, cleaned it out (very little in there) and then added water to the strainer basket before turning the pump on.

I'm headed out now to take the pump apart and have a look around. Fingers and toes crossed!!
 
Update: I took the pump apart but I think I'm confused as to what the volute actually is ... it's obviously not part of the strainer pot housing as that is a solid piece of plastic with two threaded pipe openings ... so where exactly is the volute, where would I be looking for a small slit?

Also, I have not taken the diffuser off yet but the impeller looks clean and I can rotate it with my hand.

HOWEVER, I may have found the culprit. As I was attempting to separate the 2 pump sections, a small rubber washer/o-ring (appears to be broken) was sticking out from between the wall of the diffuser and the housing plastic ... I pulled it out easily. Picture of it below. Along with a picture of an intact rubber o-ring that appeared on the ground after I pulled the pump apart - any idea where that o-ring belongs?

pump5.jpgpump6.jpgpump7.jpgpump8.jpg
 

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