Craftsman XXV chainsaw won't start

I have an old Craftsman XXV chainsaw that has not been run for 20 years. I've done some work and cleaned it up a lot but cannot get it to light fuel. It turns over well and has spark. When I pull the throttle trigger and the starter cord the carb makes a whistling sound. The fuel line seems to have a lot of air in it.

What I've done so far:

Disassembled it, cleaned the cylinder, piston, crank chamber, gas tank, and bar oil chamber, put in a new spark plug, bar oil and fuel mix.

When I pull the spark plug it sparks well, fuel seems to be getting to the engine as the plug gets wet. Not sure how to tell if the compression is good, the piston does give some resistance when it starts return, which I assume is suction. Also if I hold my finger over the carb and pull the starter cord it gets a little wet with fuel. The fuel is just kind of misting out though.

 

If the plug is getting wet, it sounds like it's getting too much fuel. It also shouldn't be pushing fuel out of the carb. If it is, you may have the piston in backwards (assuming this is a piston-ported engine) or there is just way too much fuel coming out of the carb.

 

Thanks for the reply Cheese.

Not sure what you mean about the piston being on backwards. I did not disconnect it from the crankshaft when I disassembled the engine, is there a way I can tell if it's backward?

Took apart the carb and everything there looks great, clean and shiny inside.

I'm wondering if the whistling sound is normal or does that indicate unusual air flow?

I also tried adjusting the carb Hi/Lo screws but I'm not sure which turn direction does what. When they are screwed into the carb body do they restrict fuel flow?

Going to get a pressure gauge and some starter fluid I think. Don't want to give up on this little guy

Looks like this but the craftsman version:

imgur: the simple image sharer

 

(((Took apart the carb and everything there looks great, clean and shiny inside. )) Did you install a carb kit when you had it apart.. For the price of them, install a kit...& fuel lines & a filter... It's like taking a shower with your underwear on,, Sometimes you'll be O.K.... Other times you'll have to go back & wash (rebuild)) again... LOL,,, Roger

 

If you didn't take the piston off the crankshaft, don't worry about it, it's on there right.