Stihl MS 381Not Running

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StihlSaw

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1) Disregarding the picture in the video , and I know it is asking a lot and the video doesn't convey the full din , but can anyone suggest a reason for the racket this saw is making when trying to start it ? It is an MS 381 with Stihl fuel , new spark plug , new ignition , yes it is sparking , new cylinder, piston rings and piston, but won't run.
2) The clutch has not been examined , but what is the effect of not using a locking tool to block the cylinder when examining the clutch ?

Any assistance would be greatly appreciated. Thank you
 

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Thank you for the suggestion. I have not tried squirting fuel directly into the choke. I will try it over the weekend and advise accordingly.

I have removed the needle cage from the clutch drum. There is a lot of movement when the cage is removed. Is the cage designed to prevent movement or is the movement an indication of a greater problem ?
 
Don't try to run it without clutch drum bearing. The drum and crankshaft run on the bearing/clearance.

If choke is the same as 038 saws, it may not be closing. As suggested try a shot of mix. Does it start normal when warm?

Sounds like choke problem.
Clutch drum bearing problem resolved. I will look further into the choke issue. Many thanks for your input.
 
Don't try to run it without clutch drum bearing. The drum and crankshaft run on the bearing/clearance.

If choke is the same as 038 saws, it may not be closing. As suggested try a shot of mix. Does it start normal when warm?

Sounds like choke problem.
Carburettor and fuel pump checked . Still no difference to starting. I notice the compressor valve only pops up very slightly/not fully up upon trying to start the saw. Valve is a new valve which came with the cylinder set.
 
Didn't have a plug to plug decomp hole , but suggest the valve was not fully seated . Have just gone back and checked everything around the ignition / carburettor and found that it has stopped sparking. Have re-installed wire to spark plug / spark plug is new / checked gap to flywheel / ignition module is new (genuine Stihl component) --- still no spark. Will just have to investigate further. Thanks for your suggestions and the time you have taken to try to help.
 
It was previously sparking on Stihl's recommended test in the start position , now it is only sparking in the cold start position ... has a new flywheel , new earth wire / switch wire , new ignition module .
ANy idea why it would spark in one position but not the other ... have checked the switch carefully and believe all to be positioned correctly , but obviously could be wrong. Thank you
 

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