Leaking "welch'" plugs:

[JBlack2881@aol.com]

     Over the years I've had several welch plugs loosen on my
MGA's . In 94, in Carolina, my coupe had one come loose and
blow coolant all over the distributor etc. We nursed it to the hotel
and replaced it with a rubber expansion plug. Now I'm tearing the 
coupe down will replace the rubber plug. 
     Is there a trick to putting these in? I'm getting conflicting info.
 Thanks in advance,
   J.B. from O.P. , NY
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