hi 
should the 151 350 have a breather hole in filler nut like the primary filler cap? 
the primary filler has a hole about 1mm on the side. 
but the filler for gear box under carb has just got a slotted cap with no hole, 
I was reading a post from 2008 and guy had over heating problems he had no vent on his gear box 
as mine does run bit hot I was just wondering should mine have a vent ? 
cheers