Todds Tips - Starting A Fuel Injected Engine

Well, this is a short instructional video for those of you who may have a lot of experience with carburetors, but little to no experience with

fuel

injection. When you start a

fuel

injected

engine

things are a little different at first on a carbureted

engine

if you pump the throttle you are pumping the throttle pumping that throws gas into the carburetor and you start an engine that way you can prime it with a fuel

injected

engine of fuel that doesn't work you can sit here and rev the throttle all day and all it does is actuate an air valve in the throttle body which is different than a carbureted engine so what you're using in A fuel injected engine uses the electric booster pump to prime the engine.

Now, with that in mind, you can turn on the electric boost pump all day long and if the mixture comes out, none of the fuel gets to the engine to prime it, it all stops fuel metering, so the mixture control needs to be on. activated to fire the gas into the engine from To begin with, another thing is that many people think that a continental fuel injection system shoots the fuel directly into the combustion chamber, something like a diesel, it doesn't work that way, the fuel it is injected upstream of the intake valve and then gets into the cylinder when the intake valve opens, so the moral of the story is if you prime the engine, start the engine right away, don't prime the engine and then sit back there and play with your sectional loading and a bunch of other things because something similar can happen. to a carbureted engine, if you prepare a fuel injected engine and don't start it immediately, the fuel is not in the combustion chamber, it will drain through the induction tube to a low point and then if it has a counterproductive effect . could cause an induction fire, so simply prime the engine when you are ready to start.

The next thing is that the amount of priming you give the engine is directly related to the throttle position if I turn on the boost pump for three seconds to prime the engine at full throttle. I'm giving three seconds of fuel flow on an idle fuel flow setting that's about two gallons per hour. If I do the same three seconds at full throttle, I'm now firing 12 times the fuel into the engine in that same period of time because it's now firing fuel at a rate of 24 gallons per hour, so the amount of priming you give It is directly related to the throttle position, many people will simply push the throttle on a small roads and for three seconds where the boost they will find that they do not have enough to start the engine in main mode instead of running the pump for longer, all they need to do is accelerate a little more and that in turn inject more gasoline into the engine in the priming system over the same given period of time.

Now, with a carbon start, what we're usually going to do is turn the throttle about halfway, I'll push the boost pump to high boost for about three seconds on a really cold day. I can add a second and remember that on a carbureted engine on a really cold day you give it an extra shot or two to prime the same thing here except you just leave the boost pump on for a little bit. longer, so on a normal day like today our cylinders show around 53 degrees. I'm going to turn on the electric boost pump for three seconds with the accelerator halfway at one thousand one thousand two thousand three.

I'm going to turn it off. We accelerate back and put it at idle and then start the engine and it starts immediately.