Mac 3200 stalls out if your not on the gas?

[jlightning]

So my coworker Bruce purchased a used Mac 3200 and it ran good for one season w/ no issues. He let someone borrow it last winter that left the gas in it until a couple of months ago when Bruce tried to fire it up and couldn't get it to start at all. I took it to a local guy that still works on Macs and when I got it back I handed it off to Bruce without turning it over (mistake). Bruce tried it recently (a couple of weeks after being in the shop) and couldn't get it to stay running unless you give it a good bit of gas and keep it going. I took it back to check it out and have had similar issues w/ the saw...as soon as i let off the gas it wants to stall out. I checked the muffler and the air filter and both look clear/clean. What should I look at next? Should I take it back to the shop and see if they will help me out or is their possibly something i could do myself to adjust/clean it? Thanks in advance for the help!

 

[jlightning]

So i have been playing w/ the idle screw a bit and it is running a little better but still likes to cut out if im not on the gas. There is also screws marked H and L? Can someone walk me through how to adjust this saw so it wont stall? I also read that i may need to clean the carb out due to the gas sitting in it for a winter.

 

[amateur cutter]

H & L screws are not idle screws, they are the fuel mixture screws. Run both in all the way till they stop, don't tighten them just till they stop. Back each out 1 turn & fire the saw, it should run. Let it warm up for a minute or two, then zap the throttle, if it revs up without hesitation leave the L alone, if it stutters or lags turn the L out 1/8 turn & try again till it goes up smooth & quick. Now hold @ full throttle & listen carefully, if the saw revs & screams smooth & even take the H screw out an 1/8 turn also, rev again, when the saw 4 strokes or misses slightly @ wot let off the throttle & adj. the idle screw up or down till the chain just stops moving. At this point you should be close, put the saw in the wood @ wot & if the slight miss goes away under load you're good, if not turn the H screw in very slightly & try again. Remember in is leaner & out is richer on both screw. DO NOT run the saw @ wot in a lean condition, you'll burn it up, hence the reason for the 4 stroke sound till it's under load that's actually a slightly rich condition to keep heat down in the cylinder. It's not too hard to do just be patient, & use your ears. Sometimes it's also helpful to retune for weather conditions as well, the colder the ambient temp the more fuel the saw wants at wot.

BTW wot= wide open throttle.

Hope this helps. A C

 

[jlightning]

I am ready to run this thing over w/ a steam roller! I have cleaned the air filter, checked the muffler, cleaned the carb w/ gumout, put in fresh fuel mix, checked all the fuel lines and even trimmed the ends off and reinserted into carb, and worked on tuning the carb. Im at a loss as to why this thing wont run. It will run for about 10 seconds max then bog down and stall out every time. Anything else I can do to make it work properly?

 

[wkpoor]

You could have an air leak or low compression. I check for air leaks by spraying something flammable at potential leak points while it running. Most chainsaws don't run too well if compression is below 140 but I don't know your saw. If compression is 100 or lower its a no brainer scored cylinder.

 

[jlightning]

I took the carb apart and found some gray pasty stuff in the carb so i cleaned it out and am waiting for the parts to dry before trying it again. I also took a look at the cylinder and it doesn't look scored but does have some copper color to it in spots from what i could see.

 

[jlightning]

Im done tinkering w/ this saw. I am going to take it to my local shop and have a compression test done to it to see if the piston is shot or if im missing something else.