T-Series Why are there nuts in my core plugs?!

[HighAltitudeTR3]

Hello All, wondering if anyone out there can shed some light on this… I am tearing my engine down and I can’t figure out why someone would put nuts in the core plugs? Anyone seen this before?
1953 MG TD late engine

 

[Grantura_MKI]

Those look like expandable plugs to me.

 

[HighAltitudeTR3]

They aren’t leaking, any sense in replacing? I need to replace the plug next to the engine badge as it’s leaking. Maybe it’s a “not broke, don’t fix it?”

 

[Sarastro]

If it were me, I'd change them. There's often a lot of crud built up in the block behind them, and it gives you a chance to clean that out. It's not hard to reinstall them so there's little chance of leakage.

 

[PAUL161]

That looks like it was an on-the-car fix! While everything is on the bench, get rid of them and put what belongs in there! Get the brass core plugs from Tom Lange. If your not sure how to install them, there's a lot of help here. Change all the core plugs! PJ

 

[LarryK]

The rubber expandable plugs were a quick fix to a problem. Now they are old enough, they could pop out at anytime. You can reach them, replace with proper core plugs.

 

[Sarastro]

Just to emphasize the point, here's what I found under the core plug in my TD's block:

 

[Grantura_MKI]

After cleaning, I hope you still have the return on the block to fit the proper core plugs.

 

[DrEntropy]

And it wouldn't hurt to use Permatex "Aviation Form-A-Gasket" as a sealant around the edges.