Why is my 86 mazda rx7 coolant over flow fills up to the point that it over flows and over heats new radiator new rad cars and new thermostat?

The impellers on the water pump could be rusted out and you're not getting coolant flow. The head gasket could have blown out if the engine overheated. Overheating the engine, especially many of the more "flimsey" foreign engines, will cause the head to warp resulting in head gasket failure. You can get a test strip that will sense carbon monoxide in the coolant. If you find carbon monoxide in the coolant, the head gasket is leaking.

Answer

nope rotarys dont have head gaskets !!!!!!!!!!!!!!!!!!!!!!!!!! or pistons either!!!!!!!!!!!!!!!!!! check for air in system. radiator has bleed valve on the side of inlet pipping (top hose) undo valve and fill coolant until it comes out of bleed valve, close bleed valve and top coolant off, to better insure that air is out of system, due to angle of that means raise front end of vehicle make shure that rad cap is off and heater is on at full blast hot, start engine and let it run until air is out of system and thermostat is fully opened, can determined by bubbles coming up in radiator fill housing (where the rad cap goes) once coolant all goes down and is at constant flow then thermostat is fully opened, shut off engine top off and cap it up.

First answer by Redbeard. Last edit by Drftone. Contributor trust: 33 [recommend contributor]. Question popularity: 26 [recommend question]