Have spark with plug out. no spark with plug in . What is causing this

SOURCE: Husqvarna ranger 55 chainsaw starts but quits

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!

SOURCE: poulan saw wont start has spark and fuel

Look for a pinched/bare stop-switch wire (I assume that you don't have spark now). Also, check the ignition coil core gap to the flywheel magnets (I use card stock to set the gap). Make sure the plug wire was not damaged again.

SOURCE: pull cord difficult to pull..removed from saw it

Make sure someone hasn't run this saw without the oil in the fuel mixture. It is possible it is dry and some galling is happening. Or - if this saw is equipped with a compression bleeder (for easier starting), this could be not functioning and you're pulling through the normal compression (which can be a bit feisty!). Check for misalignment of some type having to do with the pull starter - check that the cord spool isn't rubbing on the housing when you pull. Good luck.

SOURCE: 455 wont run

Make sure the muffler has not become plugged. Check the flywheel key as it may have sheared off for some reason causing the timing to be off, yet still generate sparks. Are the sparks blue and snappy? If not, check the ignition module gap to the flywheel magnets--use a thin business card for a gauge. A wide gap can cause weak spark. Hope this gets you running again!

SOURCE: no spark at the spark plug

Try this, if no spark replace the spark plug first(<$5) and retry.
It checks every part of the ignition system.
Ignition Coil Test by SmallEng.com
http://www.youtube.com/watch?v=L7WNBDRG4C4
You may need to use a jumper wire between the threaded part of the plug and the cooling fins. You do not have to bend up the electrode.

Ignition module gap
Place a business or index card between the fly wheel and coil, rotate until the magnetic attraction pulls everything tight together. Tighten the coil screws, rotate the flywheel until the attraction eases and remove the card. Ensure nothing contacts when the flywheel is rotated.

Homelite/Ryobi.com (authorized parts supplier)
https://www.gardnerinc.com/recons/disclaimer-lg.php - Agree; Choose “Product Line”; “Select OEM” & “Select Catalog” both to “Homelite Consumer Products”. A drop down list appears; self explanatory from here.
The numbers Homelite & Ryobi use do not match the numbers everyone posts. A careful inspection of your saw should find something that matches.

If you have more questions or need additional help please reply below and I will get back to you. HTH & Good Luck.
Lou
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