Coolant Fan Cycling

[Chris Kennedy]

I was testing the coolant fans on my new MKII this morning to make sure they came on automatically and, yes they did, but noticed they cycle on a tight pattern---- just under 15 seconds on, then just under 15 seconds off, then 15 seconds or so on etc. I suspect this is correct, as override feature and air conditioner operation turns them on continuously. Am I correct about this? I am making good progress learning about and working with the car--- jacked up the car and changed the tire myself, adjusted rear clamshell for smooth open/close etc.
Thanks,
Chris

 

I was testing the coolant fans on my new MKII this morning to make sure they came on automatically and, yes they did, but noticed they cycle on a tight pattern---- just under 15 seconds on, then just under 15 seconds off, then 15 seconds or so on etc. I suspect this is correct, as override feature and air conditioner operation turns them on continuously. Am I correct about this? I am making good progress learning about and working with the car--- jacked up the car and changed the tire myself, adjusted rear clamshell for smooth open/close etc.
Thanks,
Chris

Hi Chris, I spent much time testing autofan switches. In the end fitted a high temp variant to cover the times I forgot to handle it manually! My RCR with about 375bhp was tricky to get stable with water temp. But fitting a pair of Kenlowe high output fans cured the issue impressively. Didn’t worry about low intermittent setting just have them on full chat and forget about overheating!! Cheers Roger

 

[Chris Kennedy]

Thanks, I appreciate the reply and advice.

/s/ Chris

 

[Rick Muck- Mark IV]

Chris,

I have not had a SPF GT that cycled that quickly. Usually 60 seconds "on" or more. I suspect you may have a relay problem.

 

[Chris Kennedy]

Chris,

I have not had a SPF GT that cycled that quickly. Usually 60 seconds "on" or more. I suspect you may have a relay problem.

Thanks---I will look into it!

/s/ Chris

 

[Tim Terry]

Chris,
Also be sure your coolant system is burped - no air trapped. You can search these forums for more about that issue. That might cause some faster up/down cycles on temperature. I used a vacuum fill system to make sure to draw in the coolant without air being trapped. My system doesn't cycle as fast as you describe.

Tim