People may or may not appreciate this level of detail.
The Kawasaki's use the JIS (Japaneses) standard threads which are interchangeable with the BSPT (British) standard. JIS is very difficult to find so most people will use BSTP which is more available in the US.
While JIS and BSTP are interchangeable they are not identical if you look at their dimensions. The BSPT 1/8-28 is interchangeable with the stock Kawasaki cooling fittings.
I bought a BSTP tap and it lines up perfectly with the stock Kawasaki cooling fitting threads. When you compare it to a 1/8-27 NPT over a distance you can see the threads starting to become misaligned.
I see why people think it's a 1/8-27 NPT, but it isn't. The pitch and diameter are off, but if you can get them started they will go in and work.
For a $5 tap from Amazon I'll stay with the BSTP standard.
So you finally found the right solenoid valve to replace your broken one. You call to check stock on the item and the sales rep asks you what thread type you need. You ask, “How do I find out what thread type I need?” Fortunately, we’ve got you covered.
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