Dual-fuel engines are capable of operating using a mixture of two different fuels. Generally, the primary fuel is a gaseous fuel (CNG, LPG, Hydrogen), while diesel is used as a pilot ignition source, i.e. functioning on heat of compression and not a spark plug. There have been a few dual-fuel engine strategies to control the speed of the engine based on varying loads, but these require the addition of complex mechanisms to the existing systems. This paper discloses a methodology for controlling the diesel quantity during dual-fuel operation. According to the engine speed and accelerator pedal position, a gaseous fuel injector in the system injects a predetermined quantity of gaseous fuel. Based on the regulated quantity of gaseous fuel, the intake manifold creates an air-gas fuel mixture. The air-gaseous fuel mixture and a metered quantity of diesel are delivered to the combustion chamber via the intake manifold, fuel injection pump, and other components. The governor and fuel injection pump work together to measure the quantity of diesel according to speed and load conditions. During dual-fuel operation, the governor regulates engine speed by controlling the quantity of diesel delivered to the engine based on speed and load conditions. Keywords: Dual-fuel, Control Strategies, Off-Road Engines, Combustion, Emissions, Diesel Replacement