I've got a pump that has trouble starting, just hums unless I whack it with a hammer. Most articles seem to indicate I need to replace the start capacitor. I've opened up the back of this pump and all I see is one capacitor which I believe is a run capacitor. The markings are CBB65A-1; 35uF +- 6%; 370VAC 50/60 Hz. If this is the run capacitor, where is the start capacitor? This motor doesn't have a hump on top.