Help! Lawnmower zings when I try to start it!

[Sheets]

Craftsman 15.5 HP I/C OHV Hydrostatic 42" Deck/Briggs & Stratton Engine
Model: 28N707
Type: 0171 01
Code: 9511034A
This is my first time posting on any sort of forum, but I am not a great engine guy and I could seriously use some assistance.

It all started with my mower stalling on small hills when the blades were engaged, so I replaced the fuel filter, and cleaned out the carburetor with Sea Foam. This seemed to work very well, until halfway through my lawn I ran out of gas, so I filled up. After adding new (fresh) gas, my mower would die every time I engaged the deck! I tried restarting the lawnmower 3x and now I just get a zinging noise every time I turn the key. What could this be? And is it related to my mower stalling going uphill?

This is a project I would prefer to work on myself instead of taking it to the shop, so any assistance would be great!

 

[ILENGINE]

May have broke the plastic starter gear. remove the starter and look at the gear. don't twist the inner nut were the wire hooks onto the starter or you may twist the wire going to the brushes and break it off inside the starter. most of the new starters have a ring that holds the retainer for the gear on and may be a pain to remove without the proper tool and don't let it go zing across the shop of you will need to get a new one. the may reason for the engine dying when the deck is engaged in a faulty seat switch or a bad connection to the switch.

 

[Sheets]

Thanks! I'll try that first, and keep you posted on the outcome!