Got my engine out and found out how the engine could have seized. Now I've never had to deal with these plugs before. How do I put the plug back in? It seems to fit in perfect and also come out with out any force either.

Another

drill for an NPT threaded plug, get one, plug it in with a little PST.
i like using aluminum plugs, people with way more experience than me say the steel ones work just fine.

PST?

a LocTite company product - Pipe Sealer with Teflon. i've seen it both at the FLAPS in the goo's and sealants area, and the plumbing supply area of the local home stores. it's a "LocTite-type" anaerobic sealant but with Teflon to prevent galling and allow a possible future removal. little white tube, red label, PST.

Thanks for the quick reply. Do you think it would be good to convert all the plugs to threaded plugs.

i don't claim to know any more about T-IV's than what i've read here and on Rennlist - and my ownership of a 1,7 many years ago ...

i've read here that the experienced builders do that as a matter of course. hopefully, one of them will contribute an opinion to this thread ... for instance - i don't know the exact appropriate NPT plug sizes nor what drill sizes are best for achieving the best sized holes in T-IV case material for the appropriate taps.