Radiator Questions

in the photo i have a radiator exactly like this one . i need to know what the large red screw on the right side is for and the small red screw on the top left and if it matters which side is hot and which is cold on the hoses.


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Ian Anderson

Lifetime Supporter
Small hole at top is a bleed pipe back to the header tank

Large hole is for the fan switch - It is called an otter switch

Inlet would be on the left side of that photograph and outlet on the right

thank you Ian, that helps a lot


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Good morning England,
I had a few questions with my radiator Ian, since I am running a reverse rotation water pump and my otter switch connection is on the left side of the radiator (driver side in America). i uploaded a photo of the actual radiator.


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Bill Kearley

It all works the same but would it not be better to have the fan switch at the water outlet on the intake, twill turn the fan on a little sooner. I was going to put mine at the rad as well but not to shr yet. what do others think?