A quick ck is to pull the muffler.

1. You will basically be able to see the conditions of the cyl, rings and possibly a carbon issue.

2. If all looks well, troubleshoot compression, carbs adjustments/condition, fuel lines/filter, fire.

3. I h/n seen a comp/chart vs living by a rule of thumb of 100 psi or not being able to hold comp in with my thumb. I feel this could be different on newer engs easier to pull but runs great, like a low comp start.

4. Have you ever cln or adj your carb, ck the plug's cond, color of your spark? Fire/Fuel/Comp!

Good Luck and Please Share what you find. loger

Thanks, loger. I'll pull muffler next and see.

After the quick inspection with no signs of scoring?? I would suspect carb. too lean. I had that saw and 18" bar is too much for it IMO. Plus carb. needs adjusted from time to time anyway. Another thing oil mix might be in play? not enough? wear? wear equals low compression. I dought you will see wear without mic'ing piston and bore? Guess what I'm saying need alot more information and Questions answered to really have guest what could be wrong?

I looked at cyl wall and see some shallow vertical lines...does it rise to scoring? I dunno enough to say. Idle screw turned CW = no change. I'll try to figure out adjustment on High Speed Mix. Always used syn oil at 40:1. I have been testing without bar/chain, so, load is less. I keep thinking about: 75 PSI. Add 10 drops 90wt oil and get 85-90 PSI. But it idles fine. Thanks for replies.

Maybe you can let me know what I am missing. My Craftsman 36cc 16â chainsaw was bogging down the last time I used it. I cleaned everything down including the carburetor & spark arrestor . The diaphragm, gaskets were all good. It has spark and a new plug with compression at 89lb. It would not start. Then flooded. Then started but could not get it going again. I set the low & high screws at 1.5 turns out & went up to 2 full turns. Any ideas?