Found the boat leak

[dizzyspots]

So...each trip down to Baja and each morning we launch and have to run the bilge pump forever...same thing at the ramp...pull the plug and it drains forever...put the plug in...added garden house and voila! found the leak
starboard side lower engine mounting bolt
Best technique for repair? simple as pull the bolt seal it with_____ and replace..sealant suggestions?

Thanks