Radiator cap rotates all the way

2000 Acura Integra Auto

Replaced the radiator through Kragen (O’Reilly)
Didn’t come with a cap - using the existing one.
If you tighten it, it goes around through 360 degrees

How can I fix it? Are there any other caps that will fix this issue?

I had a similar thing happen once when I replaced a radiator with an aftermarket part

I went back to the place, and they explained that the new radiator takes a different cap

Yes, almost 100% a new cap needs to be secured which fits this radiator. I think when I replaced the radiator on my Corolla it came with a new cap. Anyway, this has to be addressed asap, otherwise you may experience overheating and loss of coolant., which could damage the engine.

There’s some chance the tube where the radiator screws on is out of whack. A manufacturing defect in other words. In which case there probably are not caps which fit it, and you’ll need a new radiator installed.

If this were my problem, first thing I’d do is go to my local radiator shop. They’d have the full scoop.

Yup, a new cap. just like the cap on the Aunt Jemima syrup bottle won’t fit on the Mrs Butterworth’s bottle, different brands of radiators can take different caps, too.

New cap…enough said.