How do you check an electric clutch fan?
How do you check an electric clutch fan?
To confirm the diagnosis, start with this simple test: Spin the fan as hard as you can on an engine that has not been started that day. If the fan rotates more than five times, you can bet the clutch is bad. You should feel some resistance and the fan may spin up to three times, depending on the ambient temperature.
When to test the Electro Viscous fan clutch?
One of two conditions is possible. If your fan is roaring like a jet engine after it has warmed up, DO NOT TEST. It’s already confirmed that the clutch is locked up and needs to be replaced. Normally, it will roar a little on startup and should quiet down as it warms up.
When to turn on the cooling fan relay?
The cooling fan relay is an electromagnetic switch that controls the power supply to the engine’s cooling fans. It ensures that the energy-intensive devices only run when needed, usually when the vehicle is immobile. When the engine temperature approaches unsafe levels, the vehicle’s computer or temperature switch turns on the cooling fan relay.
How can I tell if my fan clutch is defective?
Because the engine is at normal operating temperature, the PCM will not command the fan to run right away. Keep holding it while the engine gets hotter As it gets hotter, you should start feeling some tugging from the fan trying to get it going If you are getting that tugging, the clutch is working. If not, it’s defective.
What causes radial streaks in a fan clutch?
Radial streaks are another potential clue—this happens when oil escapes from the clutch and is then blown outward in all directions by the fan. Inside the fan clutch, there is a small reservoir filled with a viscous silicone-based oil. The oil flows to and from the main chamber as engine heat fluctuates, engaging and disengaging the clutch.
How can you tell when a fan clutch is engaged?
You should be able to audibly detect when the fan clutch engages, with an accompanying rush of air. At idle, as engine temperature increases, a thermal fan clutch will engage at a certain temperature. Torque-limiting fan clutches will disengage at a certain engine speed. Alternatively, an optical tachometer can be used to measure fan speed.
How does a torque limiting fan clutch work?
A torque-limiting fan clutch reacts to engine speed. A centrifugal valve opens to allow the flow of heavy silicone fluid, locking the fan blades to the pulley. At idle and low engine speeds, this fan clutch is fully engaged, gradually disengaging as engine speed increases.
When do you know it’s time to replace the fan clutch?
According to Hayden, here are some signs your fan clutch might need replaced: Fan spins excessively when engine is stopped (three or more times when hot engine is shut off). Poor A/C performance at idle or low vehicle speeds. Fan speed does not increase when engine is hot.
The cooling fan relay is an electromagnetic switch that controls the power supply to the engine’s cooling fans. It ensures that the energy-intensive devices only run when needed, usually when the vehicle is immobile. When the engine temperature approaches unsafe levels, the vehicle’s computer or temperature switch turns on the cooling fan relay.
