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If a carburetor has an electric solenoid that shuts of the fuel when you turn the ignition off. Does it really matter if you use non ethanol fuel or not?

When the solenoid is off is is closed and no fuel is in the carburetor so there should be no issue with what type of fuel you use and if you the turn of the fuel lines off or not. The carburetor should be in a dry fuel condition, correct?

Am I correct on this or just confused about the solenoid function.

Bowl should be full of fuel just stops any further flow after the key is shut off .

interesting.... when I remove the solenoid there isn't any or very much fuel in the bowl. What does that tell me? do I have an issue with something?

Hardluck said:

If a carburetor has an electric solenoid that shuts of the fuel when you turn the ignition off. Does it really matter if you use non ethanol fuel or not?

When the solenoid is off is is closed and no fuel is in the carburetor so there should be no issue with what type of fuel you use and if you the turn of the fuel lines off or not. The carburetor should be in a dry fuel condition, correct?

Am I correct on this or just confused about the solenoid function.

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Red Good said:

Bowl should be full of fuel just stops any further flow after the key is shut off .

Click to expand...

The fuel bowl should be full of fuel at all times except when ran dry. The solenoid doesn't stop fuel from flowing into the carb, and will not prevent fuel from overflowing the carb in the event of a float valve failure. The solenoid, often referred to as a fuel shutoff solenoid isn't a fuel shutoff valve. It is an afterfire solenoid The purpose is to prevent fuel from being drawn into the engine from normal valve and piston cycling and then deposited into the hot muffler were it ignites, causing the dreaded bang.

ILENGINE said:

The fuel bowl should be full of fuel at all times except when ran dry. The solenoid doesn't stop fuel from flowing into the carb, and will not prevent fuel from overflowing the carb in the event of a float valve failure. The solenoid, often referred to as a fuel shutoff solenoid isn't a fuel shutoff valve. It is an afterfire solenoid The purpose is to prevent fuel from being drawn into the engine from normal valve and piston cycling and then deposited into the hot muffler were it ignites, causing the dreaded bang.

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Thank you for the clarification on the solenoid. Very good explanation. I appreciate it.
What does it say to me if my carb bowl is not full of fuel when I remove the solenoid?

Hardluck said:

What does it say to me if my carb bowl is not full of fuel when I remove the solenoid?

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You need more gas in the carb bowl. See what is causing your lack of fuel delivery. Same thing with your car. If the gas gauge reads E, and you sputter to the shoulder, what do you think you might need to do?

Open gas cap. Shot in the dark but vent might be clogged.

slomo said:

You need more gas in the carb bowl. See what is causing your lack of fuel delivery. Same thing with your car. If the gas gauge reads E, and you sputter to the shoulder, what do you think you might need to do?

Open gas cap. Shot in the dark but vent might be clogged.

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Thank you, I guess I will need to buy a new carburetor, I have replaced the fuel, fuel filter, fuel lines, cleaned the carb, replaced the solenoid and fuel pump. drained and refilled with new gas the tanks. What's next?
Also the air filters!

Hardluck said:

If a carburetor has an electric solenoid that shuts of the fuel when you turn the ignition off. Does it really matter if you use non ethanol fuel or not?

When the solenoid is off is is closed and no fuel is in the carburetor so there should be no issue with what type of fuel you use and if you the turn of the fuel lines off or not. The carburetor should be in a dry fuel condition, correct?

Am I correct on this or just confused about the solenoid function.

Click to expand...

You are confused .
The solenoid just rams a bung up the main jets back side preventing fuel being drawn through the main jet , so that in the last few revolutions with no spark unburned fuel can not be released into the atmosphere ( a jet engine dumps around 200 gallons during take off but that is OK ) .
Now if the float bowl overills te fuel will come out of the vent hole and enter the engine via the bowl vent passage filling the crankcase with fuel .

Simply too many people misunderstand the purpose of that Anti After Fire solenoid. It just like those pushes shut cutoff valves. Even those that are used still doesn't resolved the under laying issue. I kinda like those fuel shut shut valves used on ATVs that are vacuum operated, you don't forget turn them off.

I had one earlier that though his was the carburetor instead. After received the repair bill he why I installed a vacuum fuel shut off valve when it was the carburetor that needed repairs. I told him that was because it was the source of the leak as its diaphragm had ruptured.

But I do agree the jets are one of the most polluting machine on the planet. I remembered our 911 and how clear the skies became while these jet were grounded. And it didn't hurt that a vehicles were also offlined.

Good reply, can you give me information or a place to see how to install a vacuum fuel shutoff on my BB Kawasaki fd731?
TKS

The one large enough for the Kawasaki FD731 is expensive if you use the Honda VT600CD PN16970-MZ8-U53. It is on 583CC engine where the FD731 is 675CC engine.

But there is an after market version with an shut valve that you just toss on eBay.

https://www.ebay.com/itm/403630302185

or just the valve


As for installing you need add a vacuum port in one of the rocker covers and make your own mounting bracket.

Thank you.
For the vacuum can I splice into the vac line for the fuel pump it will it not have enough vacuum?

Should be enough, just haven't had a time or chance to try this on my own mower. I didn't get to cut my own lawn until this week, that was for two months. Now I got a hay field.

Thanks