Need help-pump motor stopping...

Pump motor will run for a few minutes and then one click is heard and pump volume drops, about 30 seconds later another click is heard and the pump stops pumping altogether. I think the motor's thermal overloads are tripping, first one and then the other, but I'm not sure. Breaker is not tripping. About 5 minutes later, the pump starts back on its own and then repeats the tripping cycle. It will pump water when it's running, so I don't think the suction side is clogged.

Also, do y'all have any idea what pump and motor is this? The name plate is now worse than it looks in this photo and no info is discernible (rusted away).

Thanks in advance!

I believe there is usually only one thermal cutout in the circuit. If there were multiple cutouts they would be in series so any one tripping would cut the pump altogether. The two step shutdown seems to indicate the first click is the starter winding switch kicking in as the motor slows down, then the second click could be the thermal cutout. There is a centrifugal switch on the armature that will open once the motor comes up to speed, and conversely will close if it slows. I accidentally put 120V on a motor configured for 240 once. Under no load, such as when priming, the thing would spin up to speed, but when loaded, as when pumping water, it would slow and if loaded enough, would slow to the point the starter winding would kick in again. Then, back up to speed, slow down, and would repeat this cycle. I don't quite understand why the thermal cutout would trip unless it's a borderline trip point and being on the starter winding pulls enough current to trip it. Heating of the thermal cutout switch can be due to either high motor temperature or excessive and/or prolonged current drain.
Some questions:
1--When it first starts up is it running at full speed? You kind of indicated it is.
2--Any strange noises like it really loaded down? Loud hum etc.
3--Is the motor case hot to the touch?
4--If it's wired for 240V is there any possibility you lost one leg and are somehow applying only 120 to it?
5--Any unusual smell as in maybe a cooked winding?

Sorry...have no idea what type of pump is in the pics.
Hope this helps a little.
Al

You need a new motor. You have a Sta-Rite Dura-Glas pump. Can't tell what size horsepower you have without a little more info. Perhaps on the metal plate near where the pvc pipe comes out of the pump. A small decal about 1/2 in by 1 inch. it'll start with P2RA5 followed by a letter. Or on the motor itself, if any part of the decal is readable youre looking for HP or even a model # for the motor.

Take a close up of the labels and perhaps we can help a little further.

Well...
Motor has no identifying marks. Label is long gone-rusted away.
Took a chance and tore the pump apart and, you're right! It's a Sta-rite Dura-glas series pump, 1-HP.
It has a C105-138PEB impeller in it, which according an owners manual I found on the internet, when installed in the P2RA5E-124L Pump, makes it a 1-HP pump. The ratty silver tag near the pump discharge confirms this (I had to fill in the faded numbers/letters that were hard to read with what I learned from the impeller!).

That would make the motor a 1 HP motor - correct?
I assume I'll replace this with a 1 HP, 1.65 service factor motor, such as an AO Smith QC1102/B848?

Hmmm...Now for a crazy question: Apparently, my filter is a Pac-Fab Tagelus, 24" diameter.
Online references say that it can handle a 1 to 2-HP pump.
Could I replace the impeller in my pump with a 1.5 HP impeller (the C10-137PEB, perhaps) and buy a 1.5 HP motor? Thus having a 1.5 HP pump?
Or would it be worth it?
The current 1 HP pump/motor does push sand out on occasion.

Thanks for all your help!!

If you're pushing sand out with a 1 HP pump then you don't want to go bigger...go smaller. Excessive flow and/or pressure is what's causing the sand to blow past the filter.
Al

With a 1HP motor and a 24" diameter sand filter it shouldn't be pushing sand out, should it? I have 2 skimmers and 1 bottom suction with 4 return lines each plumbed using 1-1/2" piping. The current pump/motor combo could not handle the bottom suction, 1 skimmer and a Baracuda G4 in the other skimmer - not enough suction - G4 wouldn't move.

So what would y'all recommend? The 1 HP full-rated motor with a 1.65 service factor or the 1 HP up-rated motor with the 1.25 service factor?

I was leaning toward the 1.65 SF, full rated motor AO Smith QC1102.

Be very leary about upsizing your pump. The additional flow may work against itself overcoming the friction of the 1/5" pipe. Most often the pump was intentionally set as 1 hp because your hydraullic system was designed with a 1 hp pump. to move up in size might require larger eyeballs in the returns at the pool and or swapping out the 1.5" for 2" pipe.

If youre losing sand from the sand filter, perhaps its a crushed lateral down in the the bottom of the sand tank. When was the last time your sand was changed? If its been several years like 5+, nows a good time and you'll have the opportunity to inspect/replace a broken lateral.

Sand was changed at the beginning of the season, just prior to letting the PB go. PB claimed he checked the laterals at that time and all was well. They could have crushed / dislocated one or more while filling with sand, I suppose.

Y'all have convinced me not to upgrade my pump to a 1.5 HP and I certainly don't want to change the plumbing from 1.5 to 2 inches.

With the pump motor being so rusty, I really can't tell what was originally installed, whether it was a 1.65 service factor of a 1.25 service factor.

After reading what y'all have written, I think I'll be safe and go with the 1.25 service factor, 1 HP motor, AO Smith SQC1102. They claim it's energy efficient, drawing only 6.3 amps as compared to the 7.4 amps of the non-energy efficient pump.