Compare this with petrol engines in which you need the air and fuel to be matched to produce power. Pressure on the accelerator or throttle pedal opens or closes a valve which controls airflow into the engine; the fuel system reacts by supplying the right amount of fuel. Foot off the pedal, no power demand; foot to the floor, maximum power demand.
Bulldog Gasket Kits Caterpillar Engine (Cat Kit Numbers) Natural Gas: BD-3304-013HS,(AIO)-Cyl Head Repl,37Y,1,Non Turbo(+8S1606 VCG for long valve train engine),Non Turbo(+8S1606 VCG for long valve train engine) BD-3304-013IF: Bulldog Gasket Kits Caterpillar Engine (Cat Kit Numbers) Natural Gas