Bad new Carb? Other issue?

repperl

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Little backstory; had a bad carburetor blowing fuel out the intake. Ordered a new one and put it on and it stopped blowing fuel out the intake and ran fine. Drove around the yard 2 or 3 times and parked it. Went back to it about 2 hours later to run again and mow and it would not start again. Took off the cover to discover it was blowing fuel out the intake again. Think I just got a bad/cheap carb? Or other issue going on?
 

Scrubcadet10

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I don't think it's a carb problem, it may be a valve/valve timing problem.
 

bertsmobile1

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All that a carb does is mix fuel with the air.
Blow back is caused by
1) stuck valve
2) valve out of times with piston
3) exhaust port / muffler blocked
4) blown head gasket / hole in piston
 

repperl

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All that a carb does is mix fuel with the air.
Blow back is caused by
1) stuck valve
2) valve out of times with piston
3) exhaust port / muffler blocked
4) blown head gasket / hole in piston

Sounds like she’s getting opened up
 

Rivets

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Before you open it up, please provide us the all the engine numbers, so we can see what you are dealing with.
 

repperl

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Before you open it up, please provide us the all the engine numbers, so we can see what you are dealing with.

Briggs 19.5 hp Model: 31P6770132B1; need anything else?
 

repperl

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The compression relief hasn’t been working from time to time on start up. It will just half turn and stop. Have to cover the intake and get the engine gets turning fast enough to crank before I release. Wonder if this is causing the intake valve to stick open??
Thank for the help.
 

Rivets

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These engine are known for blowing head gaskets. If it were in my shop I would order a head gasket kit #794152 and replace the head gasket. First remove the valve cover and plug. Turn the engine over by hand and look to see if the valves are operating correctly. If they are remove the head, clean and replace the head gasket. Reinstall, torquing properly, and adjust the valves. Here is a service manual for the engine. https://docs.google.com/open?id=0B6NaqjIxWV1ybEN0LWo3azl6OUU. How you proceed is this is just my opinion.
 

repperl

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These engine are known for blowing head gaskets. If it were in my shop I would order a head gasket kit #794152 and replace the head gasket. First remove the valve cover and plug. Turn the engine over by hand and look to see if the valves are operating correctly. If they are remove the head, clean and replace the head gasket. Reinstall, torquing properly, and adjust the valves. Here is a service manual for the engine. https://docs.google.com/open?id=0B6NaqjIxWV1ybEN0LWo3azl6OUU. How you proceed is this is just my opinion.

Valves are operately correctly. Went ahead and pulled the head to do the gasket. Going to check the compression relief as well while I am already working on it. We’ll see what I find tomorrow....
 
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