In fire engine which pump is used?

carburetor

Yes. That is exactly what we use today. Most engines are powered by an exothermic reaction between gasoline or a similar fuel with oxygen.

Gear Pump.Additional answer I very much doubt if gear pumps are used in any petrol car because of the lack of lubrication. Much more likely is a diaphragm pump, which is certainly used on a lot of...

Yes, both fire and Paramedic units run diesel engines.

typically positive displacement pumps are used because they maintain a relatively uniform output. For example, in a gear pump a fixed amount of fluid is pump by each rotation of the gear. Because of...