Warm starting problem - Stihl MS362

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esean

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Original model, non-Mtronic 362. Starts fine cold, runs great once started. Hot starts, where saw has only been off a minute or two, fire immediately in RUN position (open choke, slow idle) on . Leave it off for 10 minutes and then I have issues. Manual says use START setting (partial choke, fast idle), but that doesn't seem to work. After 5-6 pulls without firing I tried full choke a few pulls, then assumed it was flooded, but plug was dry. Any chance its flooding even if plug isn't wet??? Switch back to RUN and after 20 or so rapid pulls it finally fires. Thought it needed more gas, so tried opening L screw but idle bogged down. This happened every time I left saw off about 10 minutes. This was the first I used the saw this winter. Low hour saw - max 10 tanks/yr for 8 yrs. Fresh pre-mix fuel. Air filter clean. Muffler modded, no clogged screen.
 
It sounds to me like the fuel is draining back out of the carb and it takes all of the pull overs to bring the fuel back up. I have found pump side diaphragm flaps start to curl a bit from age and lose their sealing ability even though the diaphragm material may seem to be pliable. When one of my saws start to exibit these symptoms it gets a thorough cleaning and an OEM carb kit, solved it every time.
 
It sounds to me like the fuel is draining back out of the carb and it takes all of the pull overs to bring the fuel back up. I have found pump side diaphragm flaps start to curl a bit from age and lose their sealing ability even though the diaphragm material may seem to be pliable. When one of my saws start to exibit these symptoms it gets a thorough cleaning and an OEM carb kit, solved it every time.
In that case, trying full choke a few more pulls should help. I'll play with it some more. Thanks!
 
I'm not ignoring anything. I just want to confirm that lack of fuel is the issue before doing any carb work.
 
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