Fan clutch engaging too much?

[Offroader]

I don't know why, but the fan clutch only used to engage when I drove at very high speeds in highways, but now it's frequently on.

You can easily tell when the fanclutch is on, when you get more noise from the engine.

The coolant level is normal, and the temperature indicator is on the usual halfway position.

Has this ocurred to anyone?

 

[Offroader]

Let me rephrase:

Has anyone noticed if the engine becomes noisier (excessive fan noise) when it's hotter than usual?

If yes, how often does this happen?

 

[Offroader]

OK, I guess either:

1.Gasoline 4Runners don't use a fanclutch.

2.Nobody notices when fanclutch engages.

Thanks.

 

[Offroader]

Well, there's another option:

3.Nobody here knows what the hell a fanclutch is.

 

[trd2001]

when towing, i hear it. Its not enough to bother me, i just turn the radio louder

 

[4RNR-LOVN]

Offroader, most people are probably not responding becuase this has been addressed before. Yes, the fan clutch comes on usually in temps over 100F or under extensive idling, and you definitely hear it and it will impact performance while it's engaged (at least for the V8, not sure about the diesel). The fact that it doesn't cut-off over a certain speed is the only gripe I have on an otherwise terrific engine.

 

[Offroader]

Offroader, most people are probably not responding becuase this has been addressed before. Yes, the fan clutch comes on usually in temps over 100F or under extensive idling, and you definitely hear it and it will impact performance while it's engaged (at least for the V8, not sure about the diesel). The fact that it doesn't cut-off over a certain speed is the only gripe I have on an otherwise terrific engine.

Thanks, that's all I needed to know.

 

[Koz]

The fan clutch is a viscous-coupling filled with a silicone type fluid/oil that is heat/speed sensitive. It can vary the clutch engagement based on how hot it gets or how fast it is rotating and how much wind resistance is against the blades. It is a very good and basic design that draws very little drag on the engine to operate at various speeds. You can check the coupling by visually checking it for leaks and spinning the fan manually when the engine is not running. It should not turn freely to the touch, there should be some drag. When you hear the fan roaring it is working/engaged. The hotter the fluid gets the more engagement there is.

Koz

 

[Offroader]

What happens is that I don't remember ever hearing it while city driving. Maybe it's because of hot summer days.