Author Topic: Where to begin when you saw does not run right  (Read 188 times)

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Offline jmester

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Where to begin when you saw does not run right
« on: June 11, 2014, 08:41:21 pm »
 Would like to hear from some different guys on this one and how they do it. May help some guys to know where they should start.

1- more often then not you have a fuel delivery issue. Could be carb adjustment, weak diaphragms in the carb, leaking 
    Fuel line, bad filter or a leaking impulse line, tank vent.

2- check to make sure you have good spark. Could be a bad plug, incorrect air gap, ignition module, flywheel, ignition
     Lead, spring the hooks on to the plug, a bad ground wire, or a grounded short circuit wire.

3- then I would pull the muffler and look at the piston and cylinder.

4- if all the above check out ok then I would perform a pressure and vacuum test on the crankcase to look for some
    Kind of an air leak.

Most saws will run with a mild air leak. They will run real fast or scream as some would say.  And air leak on the high side the saw will continue to gain rpms (will not hold a constant rpm)no matter if you have a real rich setting of the high speed adjustment screw.
If there are any question on how to perform any of the test or procedures to troubleshoot please ask and we will be more then willing to help. And if you are a video person and that help you learn. There are many members on here that do great informational and correct videos on saw repair. Ask and we will give you a link to there channel.

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Offline sharkey

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Re: Where to begin when you saw does not run right
« Reply #1 on: June 13, 2014, 08:27:05 am »
I start on the muffler end and work my way back.  I first look for spark and compression.  Then fuel.  Followed by a case pressure test.  I rule stuff out as I go.