No pump, the hot water rises and the cool water falls. Top hose comes out of the center/top of the head and goes to the top of the radiator. The bottom hose comes off the bottom of the radiator and goes into the side of the engine block. The tabs on my cap are broke off so I'm sure the system is building little or no pressure. I'm fairly mechanical. Have replaced the tires and entire electrical system on this thing, icluding switching the old mechanical distrubutor for an electrical one. I assume I would need to pull hot water off the top of the radiator and the cooler water off the botom and pipe it to the regulator. Im not sure about the best way to make these connections though. Can I get some type of in-line fitting to place in the hose or will I need to get fittings braised into my radiator?