What causes pump surging? (Hayward Super 2) The pump start

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JustAnswer Customer: What causes pump surging?
JustAnswer Customer: (Hayward Super 2) The pump start out fine and the pressure on the filter appears to remain steady, but the pump seams to momentarily lose prime, flows back, then again reprimes and flows forward for a short time then the sequence repeats.
JustAnswer Customer: The skimmers are not sucking air.
garrygoeson: Home Appliance Technician: Hi: My name is Garry.
garrygoeson: Home Appliance Technician: I'll be glad to assist you with your pool equip.
garrygoeson: Home Appliance Technician: Approx.
garrygoeson: Home Appliance Technician: how long after your installation of your new pump did this start?
garrygoeson: Home Appliance Technician: Is the pump installed above or below water level?
garrygoeson: Home Appliance Technician: Is it for a pool /spa combo or above ground pool?
garrygoeson: Home Appliance Technician: Answering my questions will help to give me a better idea of your situation so I can try to give you a more accurate answer.
garrygoeson: Home Appliance Technician: Since I'm not a your location, I need your input to evaluate this.
JustAnswer Customer: It started the same day.
JustAnswer Customer: It serves a combination pool/ spa and the pump is above water level.
garrygoeson: Home Appliance Technician: OK.
garrygoeson: Home Appliance Technician: Thank you for the response.
garrygoeson: Home Appliance Technician: Your description sound like there may be an air leak on the suction side of the pump
garrygoeson: Home Appliance Technician: Make sure the valves for the intake and return are lining up properly for the pool or spa side, depending on where the water is diverted to.
garrygoeson: Home Appliance Technician: Also, check the lid for the pump basket, and make sure the lid o-ring is seated properly
JustAnswer Customer: The supply and return diverter valves are fully rotated to the pool position and the strainer lid is secure and snugly closed.
JustAnswer Customer: I have not applied any lubricant the o-ring gasket because the basket says not to.
garrygoeson: Home Appliance Technician: Did you connect the replacement pump to the supply and return lines with unions, or did you plumb them direct with glue and couplers?
garrygoeson: Home Appliance Technician: Have to leave for a bit, I'll return shortly.
garrygoeson: Home Appliance Technician: Please post response and reply upon return.
garrygoeson: Home Appliance Technician: Thank you.
JustAnswer Customer: They are hard piped w/o unions.
JustAnswer Customer: I can open the diverters and see if the gaskets inside are still in good shape.
JustAnswer Customer: Thanks for your suggestions so far.
JustAnswer Customer: I've got to go to sleep.
JustAnswer Customer: I'll check back as soon as I can.
garrygoeson: Home Appliance Technician: When you open the valve covers to check the diverters, also check that the front of the diverters completely cover the opening to completely hold back the water for both the supply and return lines.
garrygoeson: Home Appliance Technician: I would also recommend to remove the pump lid and look at the o-ring, as there are times I have seen the o-ring roll and get misaligned allowing for air to enter the pump.
garrygoeson: Home Appliance Technician: Keep me posted when you get a chance.
garrygoeson: Home Appliance Technician: Thank you.
JustAnswer Customer: Garry, It looks like you had a good call on a vacuum leak.
JustAnswer Customer: I placed a DWV test plug in the strainer inlet, valved off the main drain, plugged one skimmer inlet and inserted a drain cleaning fitting into the other strainer inlet attached to a garden hose.
JustAnswer Customer: That pressurized the suction line to the pump.
JustAnswer Customer: I was able to find a couple of leaks that where letting air into the system when under suction.
JustAnswer Customer: One was at the stem of the diverter valve.
JustAnswer Customer: I will let you know if that solves the issue after I am able to complete the repairs tomorrow.
garrygoeson: Home Appliance Technician: Hopefully all the leaks are accessible enough to easily repair.
garrygoeson: Home Appliance Technician: I'll await your response.
JustAnswer Customer: Garry, The repairs were all good and there is no surging.
JustAnswer Customer: I am happy with your analysis.
JustAnswer Customer: Ed
garrygoeson: Home Appliance Technician: Ed: Happy I was able to help.
garrygoeson: Home Appliance Technician: More importantly, I'm glad the pump is running properly.
garrygoeson: Home Appliance Technician: If you need further help on this topic later, you can post it here and I'll be happy to help you again.
garrygoeson: Home Appliance Technician: Your business is greatly appreciated.
garrygoeson: Home Appliance Technician: Garry
garrygoeson: Home Appliance Technician: Ed?