2000 Calspa motor huts off from thermal overload protection.

I have a 2000 Calspa and a couple years ago the motor burnt up so I bought a new motor with dual pumps off the internet. Since new it runs fine but shuts off on high after 10 mins or so. Low will still work but high will not. After sitting or running on low for 5 mins or so, high will kick back in and run another 10 mins and continue this cycle. I have checked the power to the motor and it is constant even after high cuts off so I know it is thermal overload protection in the motor. My question is could there be something in the control board causing low or high voltage or amperage to the motor causing it to overheat or is it just the motor itself. Also I have noticed that I have very little if any suction into the strainer/filter and it used to be good. I don't know if it happened around the time I replaced the motor or if it related to the 1st problem or not. Any input greatly appreciated.