Blue plastic plug stuck in threads - what size tap?

[skunkman]

One of the blue plastic drain plugs broke on my water pump and when I removed the plug there is residual plastic stuck in the threads that I can't get out. I was thinking of tapping it out. Anyone know what size tap I need.
Thank you
Keith

 

[Bondo]

Ayuh,..... Welcome Aboard,..... The threads are 1/2- 13, but I donno's a standard tap will work, or not,.....

Never tried,.....

 

[skunkman]

I don't know much about tapping. I imagine they are NC vs NPT since the plug relies on an o-ring. Also I have never seen NPT that course

 

[QBhoy]

Happened to me loads. Learned not to tighten so much now. Haha.
but I always managed to get it out with a flat screwdriver going with the threads.

 

[alldodge]

If the plug is inside a plastic fitting, just do as QB mentioned to remove or buy another. If its in a metal one, you can apply a little heat (not a lot) but should be able to loosen it up.

Try to replace the O-ring every few winterizations and they don't need to be much more then snug.

There are some brass/stainless plugs and fittings which can be used to replace them,