Pump won’t prime because of clogged filter?

Hi all,
Looks like this time, opening my pool needs a lot of POPP :eek:
For starters, I opened "the swamp." When the pump was first started it hummed but didn’t turn. We had to spin the shaft a few times until it started properly. The pool pro who did the opening said that the pump is too noisy – indicating worn bearings.
I’m now fighting "the green" the usual way (shock and backwashes, brushing and using a robotic bottom cleaner), and I noticed that before I backwash, when the pressure goes up from 5 to 13, the pump loses its prime: it works but doesn’t move water, or does it poorly.
After the backwash, the pump’s performance goes back to normal. Is this a common behavior, or does it mean that the pump’s life is going to end soon?

I see the same with a friends pool when the filter gets clogged but in your case the 13 psi sounds low for a clogged filter. The pump should be able to deliver more than that. At least 20 psi unless you have trapped air in the pump chamber. A centrifugal pumps blocked pressure can vary greatly. A danger in running totally blocked is heating the water in the pump chamber to the point where the basket and/or plumbing starts to soften and deform. Even a very low flow will prevent this however. The issue with not starting sounds like a crummy starter switch. Happens frequently especially after sitting out all winter. If you need more info on this there are several threads dealing with this issue. Simple fix. If you can't find the info I'll dig it up and post.
Al

What keywords to use in the search?

Here's the thread:

http://www.poolforum.com/pf2/showthread.php?t=4800

and you can simply search this forum for 'switch'. Hope the pic shows as this forum is doing some strange things.

Al

There are more problems. I started a new thread of "Fixing the old Anthony vs. buying a new Hayward" instead.