As a critical auxiliary machinery in naval vessels, the V-type marine high-pressure air compressor exhibits significant dependence of its overall operational stability on the mechanical performance of the crank-connecting rod system. This study investigates the crank-connecting rod system of a V-type marine high-pressure air compressor, simulating the motion of pistons and connecting rods at all stages and deriving their inertial forces and moments. Using ADAMS software, a comparative simulation analysis was conducted on the crank-connecting rod system, incorporating flexible components, frictional kinematic pairs, and joint clearances. The results demonstrate that the flexible crankshaft absorbs a portion of the piston gas forces. Friction significantly influences the X-direction bearing load of the crankshaft in the low-frequency range, while the system exhibits enhanced dynamic stability in the mid-to-high frequency range. The clearance magnitude and different connecting-rod clearance configurations significantly affect the excitation forces on the crankshaft bearing in the load direction. Notably, smaller clearances induce larger excitation forces in the low-frequency range. This study provides a theoretical foundation and design reference for the crank-connecting rod system of differential-type marine high-pressure air compressors.