TROUBLESHOOTING
1953-1960 Classic Car Engines Troubleshooting Guide: Engine Overheats - Water Too Hot
Things to Look For:
- Slipping fan belt.
- Not enough water in system.
- Carburetor mixture too lean.
- Clogged exhaust system.
- Late ignition timing.
- Centrifugal advance fails to advance spark as engine speed increases because weights stick or because of sticking elsewhere in mechanism.
- Pre-ignition.
- Pinging.
- Water circulation impeded by installation of wrong cylinder head gasket.
- Cylinder head gasket installed incorrectly, blocking off water holes.
- Leaky cylinder head gasket permits exhaust gas to enter water. The gas bubbles interfere with the ability of the water to cool the engine.
- Water circulation slowed down by rust, scale or dirt in water jackets.
- Water distributing tube (when used) within cylinder block rusted out dented or improperly installed so that not enough water reaches some cylinders, thus causing local overheating.
- Local overheating at one cylinder (or more) due to heavy deposit of rust, scale or dirt in water jacket around cylinder or exhaust valve port.
- Water circulation impeded by thermostat which fails to open fully or sticks closed.
- Water temperature increased by thermostat which fails to open at correct temperature. Or the installation of a thermostat which opens at too high a temperature.
- Any water hose which has rotted on inside, allowing loosened strips of rubber to impede water circulation.
- The baffle in top tank may be bent in such a way as to interfere with free discharge of water from the hose.
- Vertical water passages in radiator are partially clogged with dirt, rust, corrosion or scale (mineral salts in hard water).
- Exterior of radiator clogged with dirt, leaves or insects.
- Rotting of water hose may weaken it so that pump suction causes it to collapse when engine is running fast, thus throttling the water flow.
- If water pump seal leaks, air may be drawn into the water. Air bubbles in cooling water reduce the cooling ability of the water.
- Water pump impeller loose on its shaft or impeller blades badly corroded.
- Overheats due to alcohol type antifreeze during mild weather.
The Complete Guide to Troubleshooting 1953-1960 Era American Classic Car Engines