[hypoxia]

I have not had any experience with the Headhunter pump but as for capacitor symptoms, yes they can cause a breaker to trip. They can leak the oil, become distorted, have a change in capacitance etc. Some symptoms are intermittent but eventually fail totally. I've seen capacitors that have blown up leaving quite the mess of oil.

Three must haves, IMHO, volt meter, DC amp meter, capacitance checker. You can get one meter that does all of those functions.