I heard superglue and baking soda can be used to repair plastic. It allegedly builds up to a tough surface. 

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> Wiadomość napisana przez WILLIAM WITZ <pbwitz@sbcglobal.net> w dniu 01.05.2019, o godz. 18:47:
> 
> So just an FYI. I saw some cracks starting to develop on my Fuel Expansion tanks.I lightly sanded and wipe away dust. I then used Loctite Plumber Marine Clear Adhesive to cover cracks. Let it setup for a couple of days. don't know how long this will last but so far it looks good. Anyone else have any insight on this???Thanks for your reply.Bill Witz 84 Westy Tiico