Stihl MS 170 Chainsaw -- It Won't Shut Off! -- Let's Fix It!

This Stihl MS170 Chainsaw was dropped off at my shop for repair. The customer states that the saw will not shut off by the switch and that he has to choke it to shut it off. He has also asked for a full service and look over.. Come along! Together, let's take a look at this saw and fix it for him. CHECK OUT ALL OF MY GOODIES HERE: Ultrasonic Cleaning Solution: https://amzn.to/4rD602h Ultrasonic Cleaner: https://amzn.to/3MMke1K MityVac Pressure/Vac Teste : https://amzn.to/4p2OZNU Compression Tester: https://amzn.to/4pKZCVk DEPSTECH Camera (Borescope) : https://amzn.to/4oXeYGn Echo Red Armor Oil Mix: https://amzn.to/45RuRXt Kit of Silicone Plugs!: https://amzn.to/3XKiKqt My Red Spark Plug Remover Tool: https://amzn.to/4obmV9K STIHL OEM Tool (I use this for removing fuel line): https://amzn.to/4qXg5WC Plastic Containers (I use to collect fuel): https://amzn.to/4igKsVb - - - - - - - - - Do you want to buy tools that I use at work everyday? Small Butane Torch : https://amzn.to/4coyUP3 Spark Plug Thread Repair Kit: https://amzn.to/3Oz7gVz STIHL OEM Tool (I use this for removing fuel line): https://amzn.to/4qXg5WC STIHL OEM Tool: https://amzn.to/46WsYZU Stihl Piston Stop: https://amzn.to/40qWiUK Wera A5 Torque Wrench: https://amzn.to/4rDVO9y Wera B2 Torque Wrench: https://amzn.to/4a0vtMO (I have both of these Wera's in my tool box - one for small stuff and one for bigger stuff - these two will take care of everything chainsaw related - the best quality) Protective Chaps: https://amzn.to/4tmTbub Helmet Protection: https://amzn.to/46mC9m6 Gloves: https://amzn.to/4tkaYlF Felling Wedges: https://amzn.to/3MeOrGg Chain Locker (store your chains!) : https://amzn.to/4apRtQm No SPILL Fuel Can 5L : https://amzn.to/4b4l6XI NO SPILL Fuel Can 10L: : https://amzn.to/4qqcCQn Echo Red Armor Oil Mix: https://amzn.to/45RuRXt VP Racing PRE MIXED 50:1 Fuel: https://amzn.to/4an7SVv Makita Brushless Combo Kit: https://amzn.to/443Ww6w ZEP Degreaser: https://amzn.to/4p8PQwx Compression Tester: https://amzn.to/4pKZCVk DEPSTECH Camera (Borescope) : https://amzn.to/4oXeYGn (I use this camera everyday! Sometimes, Tyler steals it to look into mower engines! It works fantastic) Tachometer: https://amzn.to/4rqGhKT JIS Screwdriver Set : https://amzn.to/3MsmOJN ( I have this exact kit for carburetor tear downs and more!) (VERY good quality!) Carb Metering Height Tools: https://amzn.to/4rwB0kS T20 T Handle: https://amzn.to/4rJYD9Z T25 T Handle: https://amzn.to/4pvAYI4 T27 T Handle: https://amzn.to/4inW2Oo 8MM T Handle: https://amzn.to/49MrsvO Ratchet Scrench Chainsaw Tool: https://amzn.to/48iEcJz 2 pack Scrench (Flat and T27): https://amzn.to/4pHlqRS Kit of Silicone Plugs!: https://amzn.to/3XKiKqt ( I often use these when I need to plug a hole for a pressure / vac test) My Red Spark Plug Remover Tool: https://amzn.to/4obmV9K (I use this tool many times a day for removing / installing spark plugs) LANG Spark Plug Gap Tool (my tool!) https://amzn.to/3LVcM45 NGK BPMR7A Spark Plugs: https://amzn.to/3Kf8pjb (These are the NGK plug that work in most Stihl chainsaws, unless it's the small plug - see below for smaller plug) NGK CMR6H Spark Plugs: https://amzn.to/4oftzM2 Plastic Containers (I use to collect fuel): https://amzn.to/4igKsVb Crankcase Splitter: https://amzn.to/44herXm (Fantastic if you are splitting crank cases - works on Husqvarna and Most Stihls ) Piston Ring Compressor Kit: https://amzn.to/4rEi7g1 Flywheel Knocker: https://amzn.to/48qHJEm Flywheel Puller: https://amzn.to/4or8ZbU Intake Blocking Plate: https://amzn.to/3XXWrOa Pressure/Vac Adapter for spark plug hole: https://amzn.to/447KdX0 Exhaust Block Off Plates and Rubbers: https://amzn.to/4ufxBby Diagnostics Kit (Great Value!): https://amzn.to/48e2S4C MityVac Pressure/Vac Tester (very good quality) : https://amzn.to/4p2OZNU ( I own this kit - amazing!) Economical Pressure / Vac Tester : https://amzn.to/4rlq6yy (I Own this kit too - for the price - you can't beat it!) Stihl Bar Nuts 6 Pack: https://amzn.to/3MaJXQD Chainsaw File 12 Pack Kit: https://amzn.to/3LNLNad Chain Depth Gauge Tool: https://amzn.to/4r9SdPA Bar And Chain Measuring Tool: https://amzn.to/3MJaFAN 2N1 Chain Sharpener 3/8P (5/32) : https://amzn.to/3N5PU25 2N1 Chain Sharpener .325 (3/16): https://amzn.to/4snjFuj 2N1 Chain Sharpener Full 3/8 (7/32): https://amzn.to/40Jyuvq