Stihl Saws - Recent Questions, Troubleshooting & Support

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Can you get a compression tester to check the compression? With the throttle wide open, the choke OFF, and the decompression valve (if so equipped) NOT engage, pull the engine over 3-5 times or until the gauge quits rising. You would like to see 90psi or more and if it is at 60 or less then it is most likely a scored piston and cylinder or bad rings. If the compression is good you need to check for spark. If it has good spark then it will most likely be fuel related. Often a complete tear down and rebuild of the carb is what is required.

Check the boot between the carb and the cylinder, it could be an air leak. also check the compression. If the piston rings are damaged then it wont have the compression to pull the fuel through. Could also be a damaged fuel line, or plugged filter.

I would check with the manufacturer using the serial number you have photographed.

Take loose the nut that holds on the flywheel. Then hold the flywheel with a pair of pliers and lift it off of the workbench, make sure the flywheel nut is even with the top of the crankshaft. As not to damage the crankshaft of the threads. Then lightly strike the nut/crankshaft until the flywheel comes loose. It should only take a couple of taps.

handles have to be removed first

Hi Harold- Here is a youtube video STIHL TS 350 Super Cut Off Saw (Pulling The Engine Apart) https://www.youtube.com/watch?v=DIlfGvFvIb4 Hope this helps.

obviously it's not getting gas. remove the carb and recheck it. some have a plastic piece over the intake and output to keep the interior clean during transit. Forgetting to remove it will cause it not to get gas. Either that or the float is stuck closed, something like that. If the carb is new out of the box, they sometimes have a piece of plastic or something inside the float bowl to keep the float from banging around during shipping ect. Check that too.

sounds like your getting air leak around a gasket

Sounds like you need to check the valve & ignition timing .

Check the fuel line in the tank to see if it's plugged. Also there could be crack or air leak in the full line not allowing gas to get sucked in. Just some thoughts if you haven't looked at this yet.

wear and tear or improper usage

Primer bulb to in tank filter - return line from carb to top of fuel tank.

Check shutoff switch, wires for grounding, magnet strength on flywheel. If OK replace ignition module .

Turn the screw gently clockwise until it won't go in any more. Then turn it anti (counter) clockwise 1 complete turn. That should enable it to start but you will probably need to adjust it when the engine is warm. Failure to start can be because of a range of causes so I suggest you check the basics first like ensuring the fuel is fresh, that there is spark at the plug and that the choke is turned on if the engine is cold.

50 parts fuel to 1 part oil.

All good answers here. If you have spark and it just quit running sounds more like water in system. The carb cleaners should help but you may need to run quite a bit through it. Remember to use care adding gasoline to avoid getting water into the tank. Also keep your tank full in storage to avoid condensation. In storing tong term add some sea foam and dump it out when you restart. Old gas turns yellow.

Most Stihl machines use 0.5mm spark gap

From [email protected] Hi kaqibso these saws are equipt with a decompression switch.It is located on the right side of the unit and has a red cap on it, pull out on it. Best of Luck......

According to Machinery's Handbook (24th ed pg 1650), there are four standard SAE spark plug threads, all metric: M18 x 1.5; M14 x 1.25; M12 x 1.25; and M10 x 1.0 Stihl OEM plug NGK BPMR7A Threaddiameter: 14mm Threadreach: 9.5mm