Craftsman lawnmower starts for 1 sec then stops

Hi! Hope everyone is doing well. I'm a complete novice here. I was given a craftsman 700 series with a briggs engine (Model: 917370690). It was sitting there for a while and had some old oil + gas sitting in it.

I completely changed the spark plug, air filter, oil (SAE30), gas and sprayed gumout at the carb from the outside. Didn't have the tools to take it out.

Tried to hold the electric start for several minutes and the engine simply does not run. A few times I did hear the engine run for a second then it shuts back down once I let go of the electric start.

From the research I gathered, I'm suspecting the carb needs a deeper cleaning or rebuilt/replacement. Any insights would be greatly appreciated!

 

I bought a new Husquavarna AWD mower. Bought proper gas and used it once and it was great. Started using a week later and it started right up and mowed half of my back lawn before it died. It was low on gas and refilled it. It started and then died. This is constant. I wouldn't think I would have a clog after one use. Any thoughts would be appreciated.

 

Generally this is a carb problem. Sometimes because of trash or water, sometimes because the autochoke is holding the choke open.

 

As Cheese suggested at least 99% of the time it's going to be a fuel issue.
Spraying from the outside was useless.
Carb. needs to come off and be cleaned and rebuilt.

 

Will clean the carb out. Thanks!!

 

The nut that holds the carb bowl on is the main jet it has one hole down the center and one across the bottom make sure these holes are clean, refer to the pic below. Have a good one. Geo

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