The paper describes some modelling aspects in finite element analysis of a small four stroke air cooled gasoline engine components subjected to thermal and mechanical loading.The authors have developed parametric model generator for connecting rod using isoparametric element. By discribing parameters numericaly the connecting rod finite element mesh is generated very quickly. It has a provision of inclusion of oil hole model also, which itself is parametric in nature. Authors have developed methodology based on ANSYS Finite element package to introduce inertia loading on connecting rod model. The concept of model generator has been extended for analysis of crankshaft for small gasoline engine. Based on results authors suggest that parametric software must have provision for local refining in finite element formulation so that using submodelling techniques stresses can be predicted accurately after convergence of results.In the analysis of finned structure of air cooled engine the paper demonstrates the contribution of fins in the strength and rigidity of the structure. In the FE analysis of cylinder head the authors confirm earlier results for the use of double cooling gallery in cylinder head design for efficient cooling performance.