Has anybody used an automatic radiator in a manual car?

[Clavurion]

Originally Posted by paramax55

The hole is .450, which is the minor diameter for a 1/2-20 thread. So a tap would go right in. But it would cut about 1/4 of the way into the .100 thick wall - if it doesn't wander to one side or the other. Then I would be cutting an o-ring groove into some sort of bolt - stainless, steel, aluminum, or plastic. Everyone hates cutting stainless. I would prefer aluminum or plastic. So I would have to order a bolt, or make it, then machine it. Or I could make a plug with aluminum I already have, which I did.

Why not use M12 for example oil plug like I suggested? I know the thread on the plug side won't be be full depth but likely sufficient when long enough and use some gasket sealant or even filling thread locker to secure it in place.

You could even try the bolt straight on when properly heated. It will melt the threads (rolling) instead of removing material with a tap.