First make sure you are getting water to it and there is no blockage in the hoses and pipes it needs hot water to flow to keep it from freezing up make sure your rad is full and the motor is not aaoverheating and has flow to block first before you by a converter it is a Nikki converter and they are not cheap also check the pressure at top there is a plug looks like has a Phillips screw driver slot of you must remove and install gauge it should get 5psi when running and cranking could see more with key on but should be about 5psi running.also make sure there is no air in block there is a Small l believe 10mm bolt at water pump open it up and make sure you have water and no air if rad low could have air in block