What does a thermostat bypass hose do?

The bypass feature allows water to flow around the engine, without passing through the radiator, while the thermostat is shut. Without it, the water will not circulate correctly creating hot spots around the engine which could lead to damage.

Do you need a thermostat bypass?

All engines that run a thermostat need to have some type of bypass provision to avoid localized hot spots, minimize the chance of steam pockets developing, promote even and rapid warm-up, and prevent water-pump cavitation.

What is a coolant bypass pipe?

The coolant bypass tube provides a passage for minimum coolant flow, so that the engine does not overheat from insufficient cooling when the thermostat is closed and restricting coolant flow.

Is it okay to run a car without a thermostat?

A car without a thermostat would never even warm to operating temperature, much less overheat. The lack of a thermostat would create a constant flow of coolant through the engine, thus a constant cooling effect on the engine. In this case though, the thermostat is not present, so this would not be a problem.

What happens if bypass thermostat?

Under normal conditions running without a thermostat will only slow down the rate that the engine will reach running temperature. It wont permanently run cold. I have a Golf GTI on the fleet at the moment which doesn’t have a working thermostat and it never reaches optimum operating temperature during normal road use.

What is thermostat bypass?

When the thermostat blocks the path to the radiator, the water pump continues to work. The solution to is a bypass passage which allows coolant to flow around the engine and back to the pump inlet whenever the thermostat is closed.

Will an engine overheat without a thermostat?

Running an engine without the thermostat can cause the engine to overheat due to the coolant passes through the engine too fast and will not let the coolant absorb the heat from the engine. If the radiator has clogged cores then it will be able to cool the engine enough and it will overheat.

How do bypass thermostats differ from non bypass ones?

The primary valve operates exactly the same as the non-bypass thermostat and opens allowing coolant to flow to the radiator when the engine is at normal operating temperature. A vehicle fitted with a bypass style thermostat must always have the correct bypass thermostat fitted.