455 Husqvarna chainsaw will not run

Sounds like fuel starvation, always start with simple things first, replace the fuel filter in the fuel tank, check the fuel hose up to the carb for signs of leaking.

Did u put fuel in oil tank and oil in fuel tank. Happens to the best.

What may be happening is that fuel pick up line and filter located inside the gas tank are floating to the top and unless tank is completly full it is sucking air causing your saw to die. Thank you.

Try removing the fuel cap for a moment to see it can be restarted immediately. If this works, check the fuel tank vent for plugging problems. Also, check for spark at the plug when it dies--if no spark, try a fresh plug gapped at 0.020". If nothing, the ignition module may be failing with heat. Good luck!

Here are a few things to consider :
- fresh fuel ratio 40:1
-new spark plug
-choke not sticking
-air fuel mixture correct
-bar and chain oil tank full, oil getting on chain
-bar sprocket in good shape getting lubed.
Please let me know what you find.

Is this you?
http://www.fixya.com/support/t3950480-no_spark_changed_ignltion_modual_no
If all this has been done it must be the flywheel or the ignition unit. I might try the local Husky dealer just to maintain my sanity. He can swap the ignition unit into a known good saw in a couple of minutes and verify good or bad. He might even be willing to honor the Husky warranty on a bad coil. Please reply with the outcome.
Lou

Ignition systems on newer saws are a solid state all-in-one package. Disconnect the kill switch wire from the ignition pack to make sure that the switch isn't broken. Use a fresh spark plug to check spark with. An old one that is black inside is likely shorted. If still no spark, replace the ignition module. Use a piece of card stock to set the flywheel magnets to module gap, then tighten screws

Check to see if your ignition switch ( on& off) switch still have both wires attached. Common problem with that saw, loose or disconnected wire

if its over a year old and you used other than 93 octane, you need to rebuild the c arb, i did an runs like new

I too have a rancher 55 and had what sounds like the same problem this week. It would start fine but run for only a few seconds at a time. I took it all apart today and found the problem - a cracked fuel line. In the places where I could see the hose it looked fine, but it wasn't until I removed the fuel tank that I found the crack...right where it exits the tank and then goes thru the housing above it. You don't need to remove the tank to replace the hose but it is easier that way. You do have to push it thru a grommet at the top of the tank. I read some other posts about checking the tank vent to see that it's not plugged up. Mine was ok so I knew it had to be something else. The vent is in a hole about the size of a pencil and is recessed about an inch into the tank on the upper right side. Its partially covered by a plastic cap that's part of the vibration damper, which can be removed to gain access to the vent. The vent tube can then be pushed out from inside the tank with the use of long needle nose pliers, but be gentle. I just loosened it then pushed it out with a finger. I put it all back together with a new hose and its running like new again!