No start chainsaw!...HELP!!!

[273hypo]

Here's the deal....
Poulan 2050 gas mix chainsaw. Very hard to pull rope and unable to start. Below are the repairs / fixes I have made.

1. Replaced all fuel lines & fuel filter and verified countless times that they are connected properly. No lines are pinched.
2. Proper gas / oil mix
3. Replaced starter pull assembly & cover with NEW parts.
4. removed and cleaned exhaust / muffler with wire brush. No real build up observed.
5. Piston does not appear scored
6. with plug removed it does pull very easy
7. Acts like its flooded so I flipped over the motor with plug removed and just a few drops of gas came out.
8. Primer bulb is full
9. I am following correct starting procedure

I know these chainsaws are considered but I had mine since 1995. I feel I'm missing an obscure rare repair but can't figure it out and sourced thru videos online with no luck. I hate to give up and throw it out with at least 20 hours of time figuring this out.
Any insight, fire away!

 

[Bob Hedgecutter]

What was it doing when it stopped?

My first thought would be a sheared key on the flywheel, creating incorrect timing.
Pulls over easy without the plug, but hard as heck with the plug in, suggests the spark is not occurring at the correct time.
Only way to confirm is remove the flywheel and check.
I am only guessing as I do not pull plastic Poolands apart, that the key is cast into the flywheel on those?

 

[jasent]

My first thought was flywheel key too. I have seen some with so much carbon on top the piston that compression was insane high also

 

[273hypo]

What was it doing when it stopped?

My first thought would be a sheared key on the flywheel, creating incorrect timing.
Pulls over easy without the plug, but hard as heck with the plug in, suggests the spark is not occurring at the correct time.
Only way to confirm is remove the flywheel and check.
I am only guessing as I do not pull plastic Poolands apart, that the key is cast into the flywheel on those?

It sat for over 10 yrs, hence fuel lines replaced. After lines replaced it would not idle. Replaced carb n plug. Then it would start but not idle. Went thru fuel lines again n found a couple fuel were switched. Then the hard rope pull issue arise. Replaced complete starter assembly and cover. Still very very hard to pull.
Not sure what mean by key. Flywheel is cast.

 

[273hypo]

My first thought was flywheel key too. I have seen some with so much carbon on top the piston that compression was insane high also

What's the fix if flywheel is issue? Repairable or scrap it?

 

[Bob Hedgecutter]

What's the fix if flywheel is issue? Repairable or scrap it?

The flywheel has a key cast into the interior of the hole that slides on to the crank taper- this key lines up with a slot (keyway) milled into the crank and assures the flywheel is in correct position to assure correct timing of the spark in relation to the cranks rotation.

If the saw had not run for a long time and symptoms are changing as you tinker with parts- odds are the key is not sheared and the timing is correct and I suggest you still have issues with fuel delivery or lack thereof.

 

[273hypo]

thank you...I will try to reassess this weekend..