my b16a has a oil leak first it was the valve cover the last person (i work wit this rookie) who worked on it used sealant on the gasket i fix that though. now its leakin by the head gasket i work wit a bunch of carb. loving old school mechanics and they claim i cant fix the head gasket leak since its aluimiun i need a new block is this true? or are the iron block heads foolin' me?