New swamp cooler blowing slow
That motor has no capacitor, it has a centrifigul switch with a start winding. You dont mention what size the cooler is but if it is the 6500 cfm model, you need to be running a 3/4 or 1 horsepower motor.
Cooler motors are not high quality anymore and I've had plenty of trouble with some newer ones, probably need to replace it.
I have two coolers on our house and one of them is only wired to run on low speed but when I turned it on this morning, it jumped to high! Go figure.
Also, when you install your new motor, make sure you adjust the pulley appropriately. If you have ductwork attached, it needs to be adjusted larger to make up for static loss. If it just dumps down into a common area, adjust the pulley out a few turns to avoid motor stalling. Best way to set it up, is to use a clamp on type meter to read what amps the motor is pulling. I dont understand the deal with the motor acting up when your pump is on, recheck your wiring at the switch and in the cooler but either way, your motor is too small for that cooler.