# Kohler Command CV15S - Gas in air box



## Ironmanx (Dec 2, 2015)

So I inherited this lawn tractor.

Not sure when the last time the oil was changed.
Buddy of mine changed the oil and air filter while i was away.

I noticed the oil smelled like gas. Didn't really see it separate like others have mentioned looking for. Seems to run fine (once started, i cleaned up the electrical connections). I assume the gas is filling up to the crank vent in the carb/airfilter housing.

I have been smelling my dip stick, neighbors probably think i'm crazy. I have not really noticed a gas small some times i think i do and then i keep cleaning it off and re dipping it and then i'm convinced nope no smell.. I do notice it looks a little thin to me.

So last night I cleaned the carb. Didn't look horrible. Saw a little piece of crud on the end of the ummm pin that attached to the float. I thought aha that must be it not sitting properly when the float floats up.

So I clean it all up put it back together. Put the air filter on with out screwing it down.
Fires right up runs great. 

Look in the airbox i see no gas. Leave it for a few minutes still no gas.
Great. I'll change the oil in the next couple of days just to be sure there is no gas in it.



I check on it this morning and there is a bit of gas down in the bottom. No where near the crank vent. Maybe like another 2"ish and it will be at the vent.
Is this normal?


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## Ironmanx (Dec 2, 2015)

Looking around I take it this is not normal and sounds like a common issue with Kohler engines. Seems like my Fuel Inlet Needle must not be sitting correctly on the Fuel Inlet Seat. (I found the real names of these parts haha)

Last night when I cleaned the carb i did not remove the fuel needle seat. I'm not even sure how that comes out. I cleaned with spray carb cleaner, a tooth brush and small wire. I assume the fuel needle seat is not the issue on these carbs as it is all metal. I assume the issue is the end of the needle is like rubber and that probably deteriorates over time.

So looks like the Carburetor Inlet Needle Seat Kit is $35 USD. In Canada that is gonna be like $50-$60 at least 

Looks like others have just went for a fuel shutoff valve instead. Which I kinda think I should have anyways just for insurance now that I know this is a common issue.

Problem is there is not that much room between the steel hose and carb:
not my pic:









So if i buy this:
http://www.canadiantire.ca/en/pdp/a...al-fuel-line-shut-off-valve-kit-0603912p.html

I may be able to use that extra hose to route around "things".
Any issue with adding extra fuel line with it being gravity fed???


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## sixbales (May 18, 2011)

Howdy Ironmanx, 

Welcome to the tractor forum.

A shut-off valve is a good solution. You can always cut off some of the metal tube if you need more room.


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## jhngardner367 (Apr 5, 2011)

The needle tip is "Viton",not rubber,and resists fuel well.
It sounds more like you have a "hot-soak" problem.
That is when,after running ,or on very hot days,the fuel expands,and may push fuel past the float needle.
Though the tank is vented,with the carb lower than the tank it happens.
Add the fuel shut-off,and,as long as the line isn't TOO long,or looped, it should be fine.
By the way,...don't smell the dipstick.
Hold a match/lighter under the end( step away from the tractor)of the dipstick,and see if it flares,or burns.
If so,change the oil.


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## Ironmanx (Dec 2, 2015)

jhngardner367 said:


> The needle tip is "Viton",not rubber,and resists fuel well.
> It sounds more like you have a "hot-soak" problem.
> That is when,after running ,or on very hot days,the fuel expands,and may push fuel past the float needle.
> Though the tank is vented,with the carb lower than the tank it happens.
> ...


Thanks. Never heard of a "hot-soak" problem.
So fuel shut off is the fix for that as well.

8PM ish after Running the machine for a several minutes after just cleaning the carb i put the tractor away. In the morning i saw fuel in the bottom of the "air box".
Got home around 8pm ish looked to see if there was more fuel in the bottom of the airbox looked to be about the same. 

I think you maybe right as if it was a needle sitting issue I would expect the amount of fuel in the airbox to get larger and not stay the same.


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## jhngardner367 (Apr 5, 2011)

When a carb "hot-soaks" the fuel inside bubbles due to heat,and expands,forcing the needle to rise enough to let fuel seep through.
Usually ,it evaporates,but if it's enough to have some,overnight I would suggest 2 things:
First,make sure the fuel cap is venting properly,and second ,install a fuel shut off,inline,and when you stop the tractor,shut off the fuel,FIRST,and let the engine run for 30 seconds,before turning off the key.
Try that,and if it still shows fuel you may want to check the crankcase breather tube,to see if it's allowing the breather unit to pull fuel back,when cooling down.


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## gman51 (Mar 22, 2016)

If you have fuel in the air box then probably the float is sticking open and gas is running out of the carb. Gas fouled oil will foul the plug and most often will not run.
Guy at work told me about this and sure enough it was the problem. I added an inline fuel shut off which solved the flooding problem.


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