Briggs surging heavily

StarTech

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How about a bad spark plug wire or connection, opening as rpm’s increase. Or spark plug itself.
Not an ignition problem.

Another hint. This is what is left of the culprit that initiate the problem. And it was not inside the crankcase.
1715778933177.png
It once looked like this
1715779167864.png
 

ILENGINE

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So a wire holder that connects to one of the starter bolts wasn't re-installed and got stuck to the flywheel magnet.
 

StarTech

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So a wire holder that connects to one of the starter bolts wasn't re-installed and got stuck to the flywheel magnet.
Basically then it got jammed under the stator creating a shorted stator which became an engine electrical brake like the ones you see on Kohler engines but with the engine still trying to run.

Here is what left of the stator. Ouch that is a $93 mistake of the other tech but the customer is having to pay the bill. Just hoping the regulator is okay. I see later after the new stator is installed and the engine is reassembled.
1715789534361.png
 

ILENGINE

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Could be worse. That part could of got wedged between the flywheel and the ignition module and broke the module mounting post off of the block.
 

Tiger Small Engine

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That part is to help hold the starter in place. A small bracket that “locks” one side in place. That is a one off and a good catch.
 

StarTech

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That part is to help hold the starter in place. A small bracket that “locks” one side in place. That is a one off and a good catch.
Actually it is to hold the stator output lead in place. And you said it very rare to have this happen but like this should never happen if the techs just keep track of the parts they are removing.
 

TobyU

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If it is hunting and surging, then it is running lean on fuel, as you know. Can only be one of three reasons: 1) air leak intake
2) dirty carburetor 3) governor (long shot).
Bingo! Somebody else says something about they've ruled out other things and fuel was one of them. I see nowhere where fuel has been ruled out and if it was it was done incorrectly because if an engine surges like this it is a mixture problem.
It doesn't always have to be at the carb is restricted and not flowing enough fuel because it could be an intake leak or something like that adding too much air to the mixture of the proper fuel but it usually is a restriction issue.
 

StarTech

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Bingo! Somebody else says something about they've ruled out other things and fuel was one of them. I see nowhere where fuel has been ruled out and if it was it was done incorrectly because if an engine surges like this it is a mixture problem.
It doesn't always have to be at the carb is restricted and not flowing enough fuel because it could be an intake leak or something like that adding too much air to the mixture of the proper fuel but it usually is a restriction issue.
Toby if you actually read the first post. Fuel issue was ruled. Please read the whole thread and you will see it was a rare engine braking from a shorted stator. Basically this this proves that their problems not related to fuel or mechanical that can cause surging.
 
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