6.5hp Briggs wont start properly

davbell22602

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Briggs 120602-0131-E1 6.5hp ohv

Let someone borrow this last year. Got it back with a bent blade. Nothing but trouble out of it ever since. Will start in 6 pulls with no blade but I hear noise like its sucking air when I'm pulling the cord. I can get to start with a new blade within 10 pulls with sucking air when pulling the cord but wont restart when hot unless I let cool down for 20 minutes to 30 minutes. I replaced spark plug, flywheel key and mower blade. I have extra engine just like it that got in a trade but dont the history on it through.

bent pushrod? stuck/bent valve? blown headgasket? Whatelse do I need to check or say heck this engine and swap the other onto it and get it running.
 

Rivets

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I would start with the head gasket unless you can pin point where it is sucking air.
 

davbell22602

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Rivets said:
I would start with the head gasket unless you can pin point where it is sucking air.

Gonna start with a compression test
 

Xbbork

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Try replacing the primer ball gasket that is located in between the air cleaner box and
The carb and clean the carb. Another thing to try is checking the coil gap. I had a 6.5hp come into my shop that wouldnt even start and thats what fixed it. When the blade got bent it could have knocked the coil loose. But i would start with the gasket and cleaning the carb out. That gasket is a common problem for this motor... Poor design
 

davbell22602

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Try replacing the primer ball gasket that is located in between the air cleaner box and
The carb and clean the carb. Another thing to try is checking the coil gap. I had a 6.5hp come into my shop that wouldnt even start and thats what fixed it. When the blade got bent it could have knocked the coil loose. But i would start with the gasket and cleaning the carb out. That gasket is a common problem for this motor... Poor design

Already checked carb and cleaned it. Replaced the air filter base gasket. Have .010 on the air gap.
 

Xbbork

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Have you removed the plastic cover on the top of the motor and cleaned that out? If not it may have grass caked in there and not letting the proper air flow in to the head causing it to over heat
 

davbell22602

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Yes been removed when I replaced the flywheel key.
 

pugaltitude

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What did you set your spark plug gap to?
On the OHV model 11 & 12 it should be set at .020".
This can sometimes cure hot start problems. Other thing is make sure the spacer between the carb and engine has not been distorted. File down with emery paper.
Other thing which iv had is if the crank has taken a knock, the flywheel magnets for the coil can lose there magnatism which can make loss of spark.
 

davbell22602

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What did you set your spark plug gap to?
On the OHV model 11 & 12 it should be set at .020".
This can sometimes cure hot start problems. Other thing is make sure the spacer between the carb and engine has not been distorted. File down with emery paper.
Other thing which iv had is if the crank has taken a knock, the flywheel magnets for the coil can lose there magnatism which can make loss of spark.

I just put in on whatever the pregap is on the torch spark plug.
 
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