Firstly- air is 100000% necessary in all internal combustion engines. What you said is actually the opposite of whats true; NO ICE (Internal Combustion Engine) will work without air (including petrol, diesel
, biodiesel, oil
combustion, hydrogen atom, etc. etc.), the air is the fuel
for the combustion, and the diesel/petrol/whatever is the trigger to the combustion.
And to understand how a "injector pump" may not be good, we must first understand the basis of how diesel engines work.
Very simply, in its essence of terms, it works like this.
1] Air comes in from the intake when the piston lowers itself (creating a sucking vacuum of air)
2] The piston moves up, compressing the air GREATLY, heating
the air up very quickly and intensely; the moment the air is at its maximum compression
rate, diesel is shot into the cylinder. This makes an extremely large explosion, because diesel is very sensitive and volatile to heat, and since the air is heated greatly, it explodes only milliseconds after injection, causing a large, powerful stroke to the crankshaft.
gases form from the explosion, rushing the piston down into the crankshaft, this is called the "power stroke" as it is the only stroke that actually helps move the engine
instead of steal power from it.
4] The piston moves up again, expelling the burned air out the exhaust
, and then readies itself for the cycle to begin again.
Now, in stroke two, the fuel pump
needs to be perfectly in sync with the computer, if it is even slightly off, or the pump is even a little weak, the whole diesel engine
becomes very weak (since if you inject diesel when compression is very low, it may only cause a very weak explosion, or NONE AT ALL), and if this is happening to every cylinder constantly, then the engine may halt, or produce very low output power.
Any other questions?