Hello fellow XK8 owners. I recently bought my 2002 XK8 with a laundry list of problems(challenges) I am slowly going down my list and making some progress. On my list of things to check out is the amount of noise that comes from the cooling fans when activated. Yesterday as I parked at the local post office the fans were going full tilt. I lifted the hood to see if indeed it was the fans making all the racket. It was.
So my question is, how much is normal? I have hot rods with electric fans and they make a fair amount of noise when operating, but not this much. Of course they don't have twin fans either.
So, if it ain't broke I will take it off my list. I know it is hard to quantify how loud is too loud. But since I don't have any other XK,s in my area I will need to count on your assessment.
Thank you all,
Lanny

 

Lanny,

The fans can normally clearly be heard above the sound of the engine when standing next to the car with the engine at idle.

It should only be the "whoosh" of air and nothing grating or mechanical like a worn fan bearing .

Graham

 

The fans operate in series (6 volts on each Fan) or Parallel (12 volts on each fan).

Normal (Series operation) is fairly quiet.

Parallel operation is VERY LOUD.

99% of the time, Parallel operation (12 volts on each fan) indicates a failed Thermostat. The Temp Gage will not show a overheat condition until the Coolant is VERY HOT.

 

......should the fans go on high with just regular driving? Or going down the hyway at moderate speed? The weather has been cool, around 50 to 60 degrees. In my experience with my hot rods the fans don't come on at any kind of speed, only when driving slow. Maybe I need to be concerned with my cooling systems capacity. Do the fans come on with regular driving?

 

The fans should not come on while driving in cool weather. Mine will come on while I wait for the garage door to open, but I would suspect the thermostat in your case. While your at it, ordering an aluminum housing from a supplier like Welsh Engineering might be wise. It is not unusual to crack the plastic housing.
There is lots of info on changing the housing on the forum, but it's not really fun.

 

Read your coooant temperature with an OBDII scanner while cruising. Normally it should hover around roughly 195-205 F if your cooling system is healthy. As referenced above, the gauge will not budge until you are over about 235 F which is borderline overheating.

 

Sounds like a faulty thermostat if those aux. fans are staying on in normal driving in 50-60 degree temperatures. I had the same problem last year and it was solved by replacing tstat.