Something I noticed. Yesteday, while "winterizing" the 1978/80 hybrid Spitfire (using the kohler engine), I noticed something strange. I drained the gas and also pulled off the fuel line to the carb to run it (the carb) dry.
Very close to being out of gas, the engine ran and sounded FANTASTIC and was extremely responsive. This duplicates its perfomance this winter (only 5 miles driven due to terrible condition in February and March in New England). During breakin, I was originally having trouble sucking gas, but realized that I had not put enough in the tank. So occassionally, the da#m thing would pull right off the ground only to then die. ANyway, after I topped off the tank, it would run "OK" but would be real sluggish on the low end. The carb (minkuni slide) has only one adjustment (which never seems to affect idle either).
What is it about a limited/reduced fuel supply that makes it run so strong??? Jets?? Perhaps Choke adjustment??? Is there another adjustment??? Would love to hear if anyone else experienced this.
Thanks.
Dan
Kohler's Performance
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harleysportster
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Kohler's Performance
Dan,
It's known as running lean. A engine will seem to run very good just before it runs out of gas.
It's known as running lean. A engine will seem to run very good just before it runs out of gas.
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400brian
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Kohler's Performance
Dan
Haven't you ever ran a chain saw? They'll just scream when they're running out of fuel.
If you are rich at idle with the Mikuni, you may need a smaller pilot jet.
You also need to remember that the Mikuni air screw works backward from most carbs.
It regulates air, so screwing it out makes things leaner, as you are admiting more air.
This is the problem with Mikunis, if you have a non stock application, you might have to go through a lot of jets before you get it dialed in.
Haven't you ever ran a chain saw? They'll just scream when they're running out of fuel.
If you are rich at idle with the Mikuni, you may need a smaller pilot jet.
You also need to remember that the Mikuni air screw works backward from most carbs.
It regulates air, so screwing it out makes things leaner, as you are admiting more air.
This is the problem with Mikunis, if you have a non stock application, you might have to go through a lot of jets before you get it dialed in.
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Kohler's Performance
I have had the chainsaw experience countless times Brian. Used to have a yamaha phazer that only ran good when it was running out of gas do to the lean condition. It was addressed with another set of carbs. I also remember squirting fuel in a motor and starting it with no carb now that was scary quite impresive how much it revved up and suprisingly it didnt grenade.
Kohler's Performance
I should have surmized this. Opps... Yes, I use a chain saw all the time (too much for my liking lately) and have expereinced the same thing.
I must admit, my instinct was to screw the one adjustment screw all the way in when trying to tune it.
Brian, that is good information to know (Out = more lean). Will keep this in mind when I uncover it in Septmeber/October and start her up.
Thanks Again!!!!
Dan
I must admit, my instinct was to screw the one adjustment screw all the way in when trying to tune it.
Brian, that is good information to know (Out = more lean). Will keep this in mind when I uncover it in Septmeber/October and start her up.
Thanks Again!!!!
Dan