Seeking troubleshooting assistance - Jonsered CS2159

[EngineerDude]

Saw is approx. 2005 vintage, not used for 2-3 years, stored w/o gas. Mixed fresh premium gas 50:1. Exhibiting low power, and when it gets warmed up it stalls and won't start, as seen here: jonsered_hot_restart_attempt. It's not the plug and not the air cleaner (same problems even w/cleaner removed). Seems likely it's a carburetion issue; specifically it seems like it's not getting enough fuel, but that's just my intuition, and I don't have enough experience to be sure. Initial start more difficult than it once was, and as soon as I start it I need to mash the throttle to prevent stall. I'm capable of repair if I can figure out what needs fixing ... i.e. fuel filter, dirty needle valve, etc., etc.

It runs better but not great (very low power, cuts way too slow even with very sharp aggressive chain) when first started, as seen here: jonsered_running_after_initial_start.

Seeking feedback and the voice of experience on the idea of this as inadequate fuel, and suggestions on specifically which mechanical element to chase and/or any other ideas on troubleshooting methodology.

Storm brought down one spar of a front yard maple, and the HOA situation doesn't provide the luxury of time to find a repair shop, etc., so I'm tackling it myself.

Thanks in advance for any assistance you can provide.

 

[lone wolf]

Saw is approx. 2005 vintage, not used for 2-3 years, stored w/o gas. Mixed fresh premium gas 50:1. Exhibiting low power, and when it gets warmed up it stalls and won't start, as seen here: jonsered_hot_restart_attempt. It's not the plug and not the air cleaner (same problems even w/cleaner removed). Seems likely it's a carburetion issue; specifically it seems like it's not getting enough fuel, but that's just my intuition, and I don't have enough experience to be sure. Initial start more difficult than it once was, and as soon as I start it I need to mash the throttle to prevent stall. I'm capable of repair if I can figure out what needs fixing ... i.e. fuel filter, dirty needle valve, etc., etc.

It runs better but not great (very low power, cuts way too slow even with very sharp aggressive chain) when first started, as seen here: jonsered_running_after_initial_start.

Seeking feedback and the voice of experience on the idea of this as inadequate fuel, and suggestions on specifically which mechanical element to chase and/or any other ideas on troubleshooting methodology.

Storm brought down one spar of a front yard maple, and the HOA situation doesn't provide the luxury of time to find a repair shop, etc., so I'm tackling it myself.

Thanks in advance for any assistance you can provide.

First initial impression is the carb is malfunctioning. You could try looking at the fuel line to see if its cracked. Also you could try to richen up the H and Low jets by turing them out counter clockwise about a 1/16 turn ea. Im thinking a new carb would cure it .

 

[Bob Hedgecutter]

Tend to agree with the carb MAY be at fault with the first video- second video kind of looks like the chain brake is engaged and wont be helping matters when you jump on the throttle.
Try taking the bar and chain off and see if it starts/runs/holds WOT any better.
Check to see if the air filter does not have a hole in it somewhere- or the top section has popped off the bottom section allowing debris into the intake.

 

[rob066]

First initial impression is the carb is malfunctioning. You could try looking at the fuel line to see if its cracked. Also you could try to richen up the H and Low jets by turing them out counter clockwise about a 1/16 turn ea. Im thinking a new carb would cure it .

Could also have the pesky plastic intake clamp leak.