Is there a problem with the fan clutch on a Duramax?

Hey All, I have a problem where sometimes in the morning after I have started the truck (and usually let it idle for about a min) I will take off and notice that the fan clutch is engaged. It will generally stay engaged for as little as 30 seconds and as long as 2-3 minutes.

What happens when a bad fan clutch goes bad?

When a fan clutch goes bad and causes your vehicle to overheat, it’s usually because the fan clutch is unable to get into its ‘Engaged’ mode. Thankfully this can be tested (indirectly) by manually locking the fan clutch into its Engaged Mode and I’ll show you how in this case study. What Vehicles Can I Apply This Info To?

What causes a fan clutch to go clockwise or counter clockwise?

This decrease in temperature causes the coil to contract and so the shaft now rotates clockwise (and thus back to its original position). This counter-clockwise and clockwise rotation of the shaft, as the bimetallic coil expands and contracts, causes the fan clutch to go into one of two modes of operation:

Why is the clutch on my AC not working?

If both of those work, then you likely have an electrical issue in the HVAC controls. Check to see if you ground the pressure switch wire and the AC clutch kicks on (check the resistance on the switch).

When does the clutch engage does the fan spin?

With a fan cluthc your fan will rotate constantly regardless. The clutch engages and locks the blade to it so that it spins faster than normal the hotter that it gets. The only time that your fan will not spin is when the motor is off. It is a common misconception that the fan will only spin when the clutch engages.

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.