Engine Motor will turn over and run but will not restart after mowing the yard.

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bertsmobile1

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  • / Motor will turn over and run but will not restart after mowing the yard.
Needing to pull the choke on to get clean running indicates a lean fuel situation in the engine.
This can be an air leak anywhere after the emulsion tube ( brass tube which sticks up in the carb.)
A low float level in the carb
Insufficient fuel supply to the carb.

If this is still happening the engine running lean will generate way too much heat for it to dissipate and that can cause it to be very difficult to restart but usually pulling the choke on full alleviates this situation.
Note it does not fix the problem , just works around it.

However I will wait for the spark test first.
The important thing is you only change 1 thing at a time or every one ends up really confused.
 
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Craftsman46

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  • / Motor will turn over and run but will not restart after mowing the yard.
bertsmobile1 said:
Needing to pull the choke on to get clean running indicates a lean fuel situation in the engine.
This can be an air leak anywhere after the emulsion tube ( brass tube which sticks up in the carb.)
A low float level in the carb
Insufficient fuel supply to the carb.

If this is still happening the engine running lean will generate way too much heat for it to dissipate and that can cause it to be very difficult to restart but usually pulling the choke on full alleviates this situation.
Note it does not fix the problem , just works around it.

However I will wait for the spark test first.
The important thing is you only change 1 thing at a time or every one ends up really confused.
Click to expand...

@bertsmobile1 = I appreciate your feedback. I will start with the inline spark tester and report my findings. Should I purchase two testers to see if each plug is receiving spark at the same time or will only one spark tester be required?

If the spark test comes show that I am getting spark to both cylinders when the engine is hot, we will move on to the next step.

If I needed to use the mower this weekend, would I be doing any long term damage by continuing to run the mower in a possible lean mixture situation?
 
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bertsmobile1

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  • / Motor will turn over and run but will not restart after mowing the yard.
If I have done my homework correctly you have the horizontally opposed twin.
These use a double ended coil and both plugs fire each revolution ( called wasted spark ),
You have a circuit from ground through one plug through the coil through the other plug to earth so if one plug fires, both fire.
If one plug does not fire then neither fire so 1 spark tester is enough.
 
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Craftsman46

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  • / Motor will turn over and run but will not restart after mowing the yard.
@bertsmobile1 = You are correct, I do have a horizontally opposed twin. One inline spark tester it is! I appreciate the follow up.
 
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buddha0360

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  • / Motor will turn over and run but will not restart after mowing the yard.
Sounds like you have some moisture in the carburetor. Drain and clean the carb bowl, and also check the fuel tank. Gas floats on water, so the engine will start and run from the gas on top. When the water/gas is agitated, the water maybe gets sucked into the carb and it won't start until the mixture sits and separates again. This is just a guess, but sounds reasonable.
 
BlazNT

BlazNT

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  • / Motor will turn over and run but will not restart after mowing the yard.
buddha0360 said:
Sounds like you have some moisture in the carburetor. Drain and clean the carb bowl, and also check the fuel tank. Gas floats on water, so the engine will start and run from the gas on top. When the water/gas is agitated, the water maybe gets sucked into the carb and it won't start until the mixture sits and separates again. This is just a guess, but sounds reasonable.
Click to expand...

The mistake that most people make is that they think gas is drawn from the top. It is not it is sucked up from the bottom of the carb bowl and the bottom of the gas tank as well. It does not hurt to clean out the carb.
 
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bertsmobile1

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  • / Motor will turn over and run but will not restart after mowing the yard.
BlazNT said:
The mistake that most people make is that they think gas is drawn from the top. It is not it is sucked up from the bottom of the carb bowl and the bottom of the gas tank as well. It does not hurt to clean out the carb.
Click to expand...

Only on new carbs with a shut off solenoid.
Older ones draw the low speed idle from higher up in the float bowl because of the reduced lift of the smaller volume of slower moving air.
So you are both right & wrong.
Very common for pull start motors to start quite fine with a bowl full of water and die the instant you throttle on.
Not so common with ride ons.
 
BlazNT

BlazNT

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  • / Motor will turn over and run but will not restart after mowing the yard.
bertsmobile1 said:
Only on new carbs with a shut off solenoid.
Older ones draw the low speed idle from higher up in the float bowl because of the reduced lift of the smaller volume of slower moving air.
So you are both right & wrong.
Very common for pull start motors to start quite fine with a bowl full of water and die the instant you throttle on.
Not so common with ride ons.
Click to expand...

And yes that is why you have to clean all the little holes in the carb when it is not running right.
 
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cambre

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  • / Motor will turn over and run but will not restart after mowing the yard.
I had same problem with my Kohler 26HP. Started fine when cool and would run all day until I killed the engine. Would not restart hot but would run all day hot. Bertsmobile1 cured my problem. He said my ignition modules were bad and he was correct.
 
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Craftsman46

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  • / Motor will turn over and run but will not restart after mowing the yard.
Just an update. I was unable to grab the inline spark tester this weekend due to being out of town. I will update as soon as the rain stops here and I can get outside and mow!
 
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