i have used a very small amount of 515 on the flat gaskets but you have to be careful on tensioning down that you dont push them out.
And you didnt clue in as to why they pushed out and continued to leak ???
You bend em" I"ll mend em" !!!!!!!
I"m not a service tech.. I"m a thermodynamic transfer analyst & strategic system sustainability specialist
Best Austin Healey In Show twice in 2013 .....All those hrs paid off .