On the concept of cracking the throttle open a bit for a warm/hot start, isn't this actually giving more air than fuel for the starting process? I totally admit that I get a bit fuzzy on this issue with the CV carb.

 

That's the same as a hot start switch.

Ride on
Brewster

 

I would think its more fuel...because when your trying to start it,and its cranking its getting air,now crack the throttle and boom here is the gas it needs to fire..

 

Yeah, but isn't the warm/start condition usually needing less fuel and more air to get fired? A cold engine needs more fuel, hence the starter jet/choke **** to provide that. A warm engine already has a more efficient atomization condition, so extra fuel may actually hinder a quick start. It seems to me that when you're opening the throttle, you're adding a bit more air to mix with the fuel which may be more optimum. When you have a flooded engine, you generally open the throttle all the way open to get as much air as possible to fire with the unwanted extra fuel. I realize there are subtle differences in the CV design vs. a cable pull slide design...and I'm leaving a pumper carb out of my statement just to simplify the discussion. And our CV carb isn't a pumper, so I'm thinking that when you crack the throttle for a hot start, you aren't immediately pulling that much fuel out of the bowl, but instead are introducing more air during that starting process. If you kept cranking, the engine vacuum will start pulling more and more fuel out of the bowl and not be beneficial.

 

Hmmm But then why after it fires you can shut it off and turn it back on and it fires on a half a click,like bang everytime.

 

I think it does that because when you kill the engine and then start it up again immediately, you have just about perfect conditions for atomization, which allows it to restart quickly. You probably have the fuel ciruits primed with fuel that was flowing just seconds ago and probably even have fuel vapors in the combustion chamber in a state the allows for easy starting.

A hot motor needs less fuel to start than a cold one. Again, I'm not claiming any authority on this, just groping my way through some principles of carbueration that I think I might know enough of to be dangerous.

 

Just thinking out loud here. Maybe the carb/fuel gets hot enough to reduce the density of the fuel to the point of not starting. By cracking the throttle, it allows the incoming air to either cool and condense the fuel or sends a stronger signal to the carb to add more fuel.

 

I don't really know what the answer is..more fuel more air..alls I know is crack it crank it boom lets go....