Hayward MaxFlo won’t turn on anymore

[Dan S]

I have a MaxFlo on my solar panels heating system. For different reasons, the solar system uses a separate plumbing system than the main one, handled by a different pump.
The pump is activated automatically by the solar control system, whenever it makes sense based on air/water temperature. However I have a Test switch to run the pump bypassing the control system.
The problem is whenever I try running the pump, I hear rattling noises coming from it for a few seconds, and then no other noise but there is no flow.

The pump is a MaxFlo SP2800X5, and I am not sure what to do now. The serial number decodes as a 2007 product, so it might be end of life?
The motor is a Century, with specs: HP=1/2; SF=1.60; PH=1; RPM=3450.

Is it worth to try a repair?
If not, what would you replace it with? I found a used WhisperFlo WFE-6 but it is rated at a much higher 1.5 HP, and it is self-priming, so I am not sure it could work for solar.
Suggestions are appreciated. Thanks in advance!

 

[1poolman1]

Test for power at the motor. If there the motor is likely bad. Get a new motor, shaft seal, body gasket and replace. Half-horse C-frame threaded shaft motor. Your existing pump is self priming.
If you want the Whisperflo, get a 1000 seal, body gasket, 1/2hp impeller.

 

[Dan S]

Thanks for the detailed information.
I am also considering a new Black+Decker variable speed 1hp pump made for above ground pools, because the pump is located below ground.
The model is BDXBTAGVAR and it is 1hp @ 3450rpm, so I could be able to run it at 2600rpm to reduce power output to around 0.5hp (if my calculations are correct).
Since it will stay below ground, I think disabling auto priming is ok (or maybe just set it to 5 seconds?).
My concern is the pump would be powered abruptly on and off by the external solar controller, typically at 10 mins intervals during a sunny day, and I am worried this would interfere with the embedded pump electronics and possibly damage it (?)

 

[1poolman1]

Black and Decker is not a pump I'm familiar with, off brand with just the name. They require constant power and shouldn't be switched on and off. There is a great difference between above ground and inground pumps, regardless of the rated horsepower. They will not give you the performance you need for your pool.