Motor damage

Hello all -

Need some technical assistance! I accidently ran my pump motor (2hp Jandy Stealth) dry in a closed loop (no water) for about 30 minutes. It popped the union at the discharge end and was very hot to the touch. I let the motor sit and I replaced the union. The pump started up and has been running since. But I have noticed that my pressure gauge at the filter is running at 17-18 psi rather than the normal 20 psi.

My question - is it possible that I damaged the pump and if so, what should I do? It seems to be running fine at the moment without any heat build up or additional noise (versus before).

Do you think this motor is going to quit on me soon?

Could this have damage the pump portion also?

Any technical help is welcome!

Thanks
John

My guess, and it is only a guess without seeing the pump, is that the motor is fine but that the heat generated somehow deformed the impeller so it is not as efficient as before. You might consider opening up the pump and taking a look at the impeller.

The motor itself would not care if you ran the pump with water or air.

I just realized that I said "closed loop". That was actually not the case, actually it was dead headed incoming and outgoing. Thats why the union popped because of the pressure created by the pump. I would think that may be stressfull on the motor and the pump.

Sorry for the misunderstanding

John

My guess is the motor is fine. As CC said, it doesn't care what the pump is doing and it is usually thermally protected. If overloaded as from sustained high pressure, it would overheat and protect itself. As you said it sounds fine, no new noises, just the slight pressure drop. As CC said that could be deformed pump parts but at this point I'd just live with it unless you feel in an inquisitive mood and feel like ripping it apart to find out for sure. Maybe some life was used up and it could die in a week (unlikely) or years from now.
Al

Thank you. I think I will rip it apart in the off season.

John

Jonny, I'll assume that the pump was primed - just give a quick look for leaks on the effluent side and underneath the pump while it's running - did the basket melt any and is there unexplained air bubbles in the pump housing? I ask because you cavitated the water and that can effect these areas - if the answer to any of my ?s is 'yes' let us know and we'll help you fix it.

Waste -

Thank you for the advice. Looks like everything is fine - no air leaks or melted parts. The only thing I see is a very very small drip underneath the motor. Maybe a teaspoon of water over the day. I will take it all apart over the winter and fix any problems then as long as it doesn't develop into anything worse.

Thanks
John

John, glad to hear that no real damage was done.:) Keep in mind for this winter when you rip the pump apart to have a new shaft seal assembly - it's what's causing your leak (it got a little too warm and slightly deformed)

don't do what i did by the way. had a pump that was leaking on the motor side of the bell housing so i took it apart..the instruction manual for the sta-rite was great in terms of how to tear it down (my first time). what i should have done though was the seal was actually about 5 separate pieces. i took them apart paying attention to how it went together and left the pieces apart on my bench..then i got caught up in something else for a few hours, came back to reassemble and forgot how everything went together. so i thought..no problem..there's an exploded diagram in the manual on the pdf online..problem is, the pictures are way too tiny and all references i found basically showed it assembled! after cursing my stupidity and staring at the thing for half an hour, i took a guess on what seemed logical to my brain anyway..lo and behold it worked out fine and no more leaks. in hindsight, i would have done 3 things:

1) for the 10 minutes it would take for me to disconnect the motor, i'll bring it in the house next winter. what i thought was the motor seal may well have simply been water coming off the ring on the bell housing and the big o-ring shrunk a bit over winter as i simply put the old seal back together, used some non hardening gasket in the right places and everything is fine. if i had run it the way it was for awhile until it was good and warm, it might have been fine. taking it in the house should alleviate any cold shrink on the seals and given it was a newly rebuilt motor, it wouldn't have hurt after last season to tap the big ring and tighten it a bit and torque the 4 bolts holding the motor onto the rest of the pump. didn't occur to me until after i was done:)

2) if i do have to replace a seal, i will stack the pieces in order of assembly. (the good news is that the company who sold me the pump are sending me a complete rebuild kit including the seal, o-rings and the round plastic thingie inside..i think it's about a 100 dollar kit that they are sending, just to be on the safe side. cheaper for both of us then the time for them to rebuild and the freight from canada to the u.s. and back)

3) don't push the pump housing pieces together with the end cap off if yours has one! that starter switch is a tad flimsy and i snapped it in half. i used the switch from my spare sta-rite pump..but was able to jb weld the original switch together and it would work fine:))

4) hmmm..i said 4 things..oh yeah, have a drink when i get frustrated:)

i expected taking apart and putting back together would be rather daunting first time out..aside from my stupidity with the seal and switch, it was easy as can be:)

Tenax -

Thanks for the great info! SHould make my life easier learning from your mistakes;)

John

no problem..i'm just happy "I' was happy to learn from my mistake too without it costing me a brand new pump:)