Is an engine coolant temperature of 65°C to 70°C normal?

[McStella]

An engine coolant temperature of 65°C to 70°C is normal. Here are the relevant details: Engine temperature too low: This can make the air-fuel mixture difficult to ignite or cause delayed combustion, resulting in reduced engine power. The engine oil becomes thicker due to low temperature, increasing viscosity and resistance to moving parts. Incompletely vaporized fuel washes away the oil film on friction surfaces like cylinder pistons and piston rings, dilutes the oil, accelerates component wear, or causes incomplete combustion of the mixture, increasing fuel consumption. Engine temperature too high: Excessive thermal expansion of air reduces the engine's volumetric efficiency, disrupts the air-fuel ratio, enriches the mixture, leads to incomplete fuel combustion, and also increases fuel consumption.