Methods and systems of controlling operation of a dual fuel engine are provided, comprising determining a target exhaust temperature, sensing an actual exhaust temperature, determining an exhaust temperature deviation by comparing the actual exhaust temperature to the target exhaust temperature, comparing the exhaust temperature deviation to a threshold, adjusting at least one of an intake throttle, a wastegate, a compressor bypass valve, an exhaust throttle, a VGT and engine valve timing when the exhaust temperature deviation exceeds the threshold to control charge-flow to the engine, and continuing the adjusting until the exhaust temperature deviation is less than the threshold.

A mechanical fuel lockout switch for a dual fuel engine includes a mechanical fuel valve actuatable between a first position and a second position to selectively control fuel flow to the dual fuel engine from a first fuel source through a first fuel line and a second fuel source through a second fuel line. The mechanical fuel lockout switch may also include a fuel lockout apparatus coupled to the mechanical fuel valve. The mechanical fuel valve may be configured to allow communication between the first fuel source and the dual fuel engine and prevent communication between the second fuel source and the dual fuel engine while in the first position, and prevent communication between the first fuel source and the dual fuel engine while in the second position.

A generator and off-board fuel delivery system is disclosed. The generator is configured to operate on one or more fuels, including on a gaseous fuel supplied from a pressurized fuel source through a gaseous fuel line. A fuel regulator system is located off board the generator and is configured to regulate the gaseous fuel supplied from the pressurized fuel source in a first stage, with the gaseous fuel regulated down to a reduced pressure in the first stage. A second stage of the fuel regulator system regulates the reduced pressure gaseous fuel, with the reduced pressure gaseous fuel from the first stage regulated down to a desired pressure in the second stage for delivery through the gaseous fuel line to operate the generator.

Various methods and systems are provided for a method for a multi-pressure fueling system. In one example, the multi-pressure fueling system includes providing a first fuel delivery pressure enabling high pressure direct injection of a fuel at a first injector and a second fuel delivery pressure insufficient for high pressure direct injection, at a second injector, based on engine operation.

A supplemental fuel system includes a fuel mixer. The fuel mixer includes a nozzle and a stem. The nozzle is configured to be positioned within a conduit of an air supply system for a compression-ignition engine. The nozzle has a body defining a first inlet positioned at a first nozzle end thereof, an outlet positioned at a second nozzle end thereof, a second inlet positioned between the first nozzle end and the second nozzle end, and a nozzle passage extending from the first nozzle end to the second nozzle end that is configured to receive air flowing through the conduit. The stem has a first stem end interfacing with the second inlet. The stem is configured to extend through a wall of the conduit such that a second stem end is positioned outside of the conduit.

Methods and systems of controlling a dual fuel engine with at least two banks of cylinders are provided. The method may include sensing at least one of temperatures of exhaust from the at least two banks and a pressure of an intake manifold of the at least two banks, and adjusting at least one of a gas flow, a charge flow, or an air flow to one of the at least two banks to balance one of exhaust temperatures of the at least two banks and intake manifold pressures of the at least two banks.

Various methods and systems are provided for venting fuel lines in a dual-fuel engine. In one example, a method may include in response to an engine shut-down request, venting fuel lines to remove hydrogen from the fuel lines.

A fuel separation system includes a fuel separator configured to receive a fuel stream and separate the fuel stream, based on a volatility of the fuel stream, into a vapor stream defined by a first auto-ignition characteristic value and a first liquid stream defined by a second auto-ignition characteristic value, the second auto-ignition characteristic value greater than the first auto-ignition characteristic value; and a heat exchanger fluidly coupled between a fuel input of the fuel stream and the fuel separator, the heat exchanger configured to transfer heat from the vapor stream to the fuel stream, and output a heated fuel stream to the fuel separator and a second liquid stream defined by the first auto-ignition characteristic value.

Methods and systems are provided for operating a vehicle including an engine and a fuel system. In one embodiment, a water drainage system for a fuel system comprises a fuel tank, a fuel-water separator in fluid communication with the fuel tank, and a purge tank in fluid communication with the fuel-water separator and the fuel tank, the purge tank separate from the fuel tank. The water drainage system further includes a fuel property sensor for detecting a presence of water and a purge line in fluid communication with the purge tank for removing fluid from the purge tank, a flow of the fluid from the purge tank controlled by a check valve.

Methods and systems of controlling a dual fuel engine with at least two banks of cylinders are provided. The method may include sensing at least one of temperatures of exhaust from the at least two banks and a pressure of an intake manifold of the at least two banks, and adjusting at least one of a gas flow, a charge flow, or an air flow to one of the at least two banks to balance one of exhaust temperatures of the at least two banks and intake manifold pressures of the at least two banks.