Walked out to find my pump running dry. . .

brackishpoolboy

Active member
May 16, 2009
27
I run my pump for 7 hrs a day using a salt water chlorine generator. I walked out yesterday to find it running dry, and it may have been running dry for a few days.

I have lived here for 4yrs and I've never serviced the pumps in any way.

I'd appreciate some help trouble shooting.

When I fire it up, I hear the motor running and the impeller turning/whining as is usual when priming, though it is a bit more struggling sounding. I get no water movement at the skimmers by the pool, nor output at the returns.

My prime suspect at the moment is the multi valve on the sand filter. One time this Spring it seemed to not engage well after a backwash/rinse, and I had to re-seat it for water to flow. I think the whine of the pump struggling against a closed output is what I am now hearing. So a check of the valve as well as an inspection/maintainance of the pump seem in order. . at least.

Here is my pool as shot from the entry of the pump house:

IMG_5220.jpg


Here is my plumbing:

IMG_5221a.jpg


IMG_5224a.jpg


If I loosen the band at the blue arrow and slide the motor out of the way, I'll have full access to the wet end for inspection/repair, yes?

I note that the little stainless nipple (at the convergence of the blue/green lines) is missing on the other side. HTis is the point on which the handle pivots when adjusting the valve. I don't know how long it's been this way. It's absence obviously torques the handle/balljoint out of its usual pivot/rotate motion.

So any guidance for a handy but ignorant fellow in need?

The salt water generator I installed has worked like a charm. You should have seen the Rube Goldberg jungle gym that was my plumbing before the install. Much better flow now, too, as a result.
 
You can get to the inside of the valve by taking the screws out, you don't need to remove the valve body from the filter.

If you haven't already, you should check all the obvious places: skimmer basket is clear, pump strainer basket is clear, multi-port valve is in the correct position, etc. Also, take the pump strainer basket out and look underneath it and check to see if there is anything there.
 
Hey bpb, welcome to TFP!!

The nipple you speak of is the end of a pin and it looks fine :cool:

Jason covered what could have caused this issue, once you solve the problem and get flow going again, check the underside of the pump for a drip, also the effluent port on the pump housing for leakage - running a pump 'dry' often will heat things up so much that the shaft seal assembly will fail and heat up the inlet and outlet male adapters :( The fixes for these are pretty darned easy and we can help you do it (I'd also like to see a union on the line from the pump to the filter, and so will you, if you need to change the seal assembly :wink: )

Another little note - you used non pressure fittings for your re plumb :shock: It would have been preferable to use schedule 40 fittings! I seriously doubt this will ever cause you trouble, though. :)

What surprises me is the suddenness of the loss of prime. A massive air leak could describe it, but seems unlikely. How are those SP 723 valves doing? Do you loosen the compression nuts before opening/ closing them and re tighten them afterwords?

Thanks for the pics :goodjob: - we'll stick with you to help you find and fix the problem(s)
 
waste said:
Hey bpb, welcome to TFP!!

The nipple you speak of is the end of a pin and it looks fine :cool:
Yeah, but it looks like it could stick all of the way through to the other side, offering support on both sides to pivot around. Having now taken the top off, I see that even if the pin isn't positioned right, the mechanism is not likely to have been unduly stressed. The mechanism is much simpler than I had imagined. The only problem I see in there is that the contact area of the gasket has largely dissolved and could use replacing.

Oh, and the guage is stuck on 15psi. I need to replace it as well. Is it neccessary to use OEM guage, or is there a standard aftermarket variety that would do or even be better?


I'd also like to see a union on the line from the pump to the filter, and so will you, if you need to change the seal assembly :wink: )

I bought three true unions while at lowes last night. I expected I may need to remove the multivalve or the pump.


How are those SP 723 valves doing? Do you loosen the compression nuts before opening/ closing them and re tighten them afterwords?


I presume those are the pair of union/valves on the input side of the pump. I have never had to use them (I use the pivoting cap in the skimmer well if I need to isolate the input from one skimmer or the other), but are you saying that I should loosen the union everytime i adjust the valve?

skimmer basket is clear, pump strainer basket is clear, multi-port valve is in the correct position, etc. Also, take the pump strainer basket out and look underneath it and check to see if there is anything there.

All good

I turned on the pump with the multivalve cover off. Even with no head, the pump could not self prime.

It's time to get a look inside the pump wet-end, I think.

thenks of r the help
 
Sent to the store by the wife, and stopped by the pool store (shudder). I picked up a new gasket and a Leslie brand pressure gauge. the gauge fit right in. The gasket's going to take a bit of work, scapping out the old one. The clerk recommended silicone sealant for placing the gasket and sold me a tube (< $2). Going to pentair's site right now to research. Any tips?

Still have not pulled the pump.
 
gasket is in, guage is in. You can see the sorry state of the old gasket. Lots o scrapin'.

IMG_5226.jpg


I pulled the motor and everything looks ok. The impeller spins when powered. See anything wrong?

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I'm beginning to wonder if I have a leak at one of the unions on the feed end, allowing air into the system. I dont hear any hissing. I'll break them down and put silicone grease (NOT silicone sealant) on the gaskets to be sure, if the motor work doesn't bear fruit.

Aside: I've been meaning to shopvac that little room for over four yrs. Full of gravel and leaves and Crud. It's spic and span, now!
 
I plan on replacing the o-ringthat seats where the screw driver is going through, at the inlet. The old one got rolled on insertion and is now permanately twisted. It never leaked, though.

Anything else I should do while I have it apart? Replace the shaft seals? Replace the bearings (don't sound bad)?
 
Since the pump ran dry for an undetermined length of time I'd replace the shaft seal at least. While I had it apart I'd probably replace the bearings too. You can get them cheap at a bearing supply house such as Motion Industries.
 

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Well, I ordered bearings, a shaft seal, a couple of orings, and a bearing puller. I'll get an education in basic motor repair/maintainance, and a tuned up motor to boot, While this is bound to be quite an adventure, I dare say none of this is likely to address my original problem.

I do run a kreepy krawly. The pressure changes that drive the motion strike me as being "bad" for th epump.

Any other thoughts? and please stay tuned ofr the repair. I'm likely to need a bit of guidance.
 
Thanks guys. Now I wait for delivery. It will likely be here befor I could have gone out and bought the stuff, unless Leslie's stocks it all. Even then, couldn't get til this wkend.

None of the pump/motor maintainance I intend to perform appears related to my original problem. Other than a more thorough search for leaks on the infeed side (once the pump is back together), any other thoughts on a culprit?

Sitting here waiting while my pool turns green.

Hey Rambler, you know what separates a coonass from a dumbass?








Mississippi :lol:
(teehee, please dont sabatoge my repairs)
 
Just an update, re;laced the bearings and seal. The seal clearly had a small chronic leak. I also gave every bolt on every joint on the infeed side a 1/8th turn, then primed it (filled the prefilter bucket) and it fired right up. I don't know how what I did could have fixed the problem, maybe the lid on the prefilter bucket was loose? WHo cares, it works!!

Since I had the tools out there and I was feeling handy, I also changed the seal on the polaris accessory pump too. It also clearly had a small chronic leak.

Thanks to everyone. I love knowing this site is here when I need it!
 
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