460 troubles

[Ohio_Bill]

My 460 ms seems to have developed pre ignition troubles.i hope that is the correct term to use .when i try to start it will pull the starter rope out of your hand .After its started seems to run ok .

[joe_indi]

The engine might have excessive carbon deposits. Get it decarbonised. You could also try increasing the spark plug gap to 0.7mm from the usual 0.5mm.

[Ohio_Bill]

Thank  you ,i will reset
the plug and give it a try.

[kenskip1]

This could be interesting. What is your oil mix ratio? Does the saw sit and idle for any length of time? To much "rich" oil could be accumulating in the cylinder. As we all know that oil will not compress thereby pulling the rope from your hand.Idling will allow oil to again accumulate causing the symptoms you have described.Have you tried pulling it with the switch in the OFF position? How long is the starter rope? Has it ever been shortened?If so you will be loosing mechanical leverage once again causing your symptoms.Hope this will assist you, Ken