Bogging???

Harquebus

Well-Known Member
#21
FYI: High octane gasoline is not "Rocket Fuel".

The octane rating is the measure of a fuel's ability to resist "knocking" or "pinging" during combustion, caused by the air/fuel mixture detonating prematurely in the engine. That mishap is a feature of engines with a high compression ratio--the air fuel mixture can ignite on its own before the spark fires because of the heat generated from the compression.

You're largely wasting your money on 94 octane gas.
Furthermore, do yourself a favor and run 100% gasoline if you can (with no ethanol) as alcohol hates carburetors and seals and gaskets.
 
#23
I just pulled off my carb which is idling fine took a pic of the slide height and checked where my air fuel mixture screw was set and it was at 1.5 turns out. I dod not remove the float bowl and jet so I do not know what pilot it has. So start with setting your slide height so it looks like mine and set air fuel to 1.5 turns as a starting point. That still does not explain why you have a eratic idle I suspect either fouled plug, air leak, or fuel flow issue.
the spark plug is black so i’ll get a new one and i’ll check the garb right now
 
#24
I just pulled off my carb which is idling fine took a pic of the slide height and checked where my air fuel mixture screw was set and it was at 1.5 turns out. I dod not remove the float bowl and jet so I do not know what pilot it has. So start with setting your slide height so it looks like mine and set air fuel to 1.5 turns as a starting point. That still does not explain why you have a eratic idle I suspect either fouled plug, air leak, or fuel flow issue.
 

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#25
The slide height and the idle air screw both work together. If the slide height is adjusted it allows more or less air in, then the idle mixture will change so the idle mixture then needs to be readjusted in that order. Now if you played with both and it made no difference then you need go no further till that issue is fixed. First do not keep adjusting things and changing other things not related to the idle. So if you focus on the idle you have only a few things that could be causing the erratic idle. First pull the sparkplug and make sure its not black or fouled. Best to start with a new plug if in any doubt or you will be chasing your tail. Next make sure you do not have a air leak. Next step is to remove carb from the rubber spigot (you do not have to take off anything just get it off so you can eyeball the back of the slide to see how high it is from bottomed out. it should be opened. it should not be opened more than 3/32 of an inch. I'm not sure about your pilot jet size as that could be an issue. I would have to go look at one of mine as I don't remember what my sizes are on mine. The main jet does nothing for getting your idle set so ignore that for now until you get the idle issue fixed. If anyone else had used a 28 on here they can chime in on the correct size that worked for them.
I just pulled off my carb which is idling fine took a pic of the slide height and checked where my air fuel mixture screw was set and it was at 1.5 turns out. I dod not remove the float bowl and jet so I do not know what pilot it has. So start with setting your slide height so it looks like mine and set air fuel to 1.5 turns as a starting point. That still does not explain why you have a eratic idle I suspect either fouled plug, air leak, or fuel flow issue.

Some great info here Gabriel...
 
#26
just curious...how can that carb work with a governor? Why would anybody want to remove a stock carb and even try to get one of those carbs to work on a stock engine?
Gabriel, do you still have the original carb?
 
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