I bought a Koyo recently and it has a hole for the stock coolant level sensor. I've already junked my sensor and really don't want to tap my new radiator. Does anybody know the thread pitch?

 

Well I emailed Koyo and they just told me to reuse the stock sensor....

 

Measure the inner diameter, then check a ansi metric internal thread and use the inner diameter to match a internal thread minor diameter.

Go to a hardware store and purchase several thread pitches and try them out gently by hand.

 

Well akins website list the thread pitch as m11.5 x1.25.... So looks like I'm buying a sensor
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