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General Forestry => General Board => Topic started by: Bigmikessmallen on September 08, 2017, 09:53:39 PM

Title: Honda motor no spark
Post by: Bigmikessmallen on September 08, 2017, 09:53:39 PM
I have a honda gx390 thats not getting and spark, i tried everything new coil and plug cleaned flywheel, ground bypass low oil bypass. I am so stumped any help would be greatly appreciated.
Title: Re: Honda motor no spark
Post by: Hilltop366 on September 09, 2017, 11:52:24 AM
Hi and welcome, I'm guessing you already disconnected the kill switch but thought I'd throw it out there. What are you checking the spark with? If outside or have bright lights it is sometimes hard to see a little blue spark better to test in low light. Did you test the new spark plug on something else?
Title: Re: Honda motor no spark
Post by: Bigmikessmallen on September 09, 2017, 01:46:36 PM
Yup tested the spark at dusk couldnt see anything. Tested new plug in another machine it works aswell as the old plug works to i just bought a new one in case. Ya i disconnected the grounds, low oil switch and tried again but nothing. Someone said it could be a bad flywheel in all my years of working on engines ive never seen a bad flywheel is this even possible?
Title: Re: Honda motor no spark
Post by: Hilltop366 on September 09, 2017, 06:02:51 PM
I have never seen it but I have stuck a screwdriver on a few flywheels to check when scratching my head trying to find the problem.

So if the magnets are good and you have set the air gap to the correct amount, the kill switch is disconnected the plug is good there is not much left.

Did the new coil come with a spark plug cap or are you reusing to old one?
Title: Re: Honda motor no spark
Post by: Bigmikessmallen on September 09, 2017, 06:23:49 PM
Nope it didnt but i tried one off another 390 and it works. Lol i think ive tried everything. In all.my years fixing small engines ive never come across something like this.
Title: Re: Honda motor no spark
Post by: Bigmikessmallen on September 09, 2017, 06:56:44 PM
Is there a fuse behind the electronic ignition that might be blown?
Title: Re: Honda motor no spark
Post by: Kbeitz on September 09, 2017, 07:08:55 PM
Did you put the new coil on backwards ?
Title: Re: Honda motor no spark
Post by: thecfarm on September 09, 2017, 08:24:50 PM
Does it have a low oil sensor?
Forget it,I missed where you all ready tried that.
Title: Re: Honda motor no spark
Post by: coxy on September 09, 2017, 08:48:01 PM
take the coil off the other 390 and try it maybe a new coil but iv seen them bad
Title: Re: Honda motor no spark
Post by: Bigmikessmallen on September 10, 2017, 05:58:12 PM
Ok guys i did evrything mentioned. New coil on other motor to test coil is fine aswell as the old coil is fine.
I figured that after changing all the spark components to new that it HAD to be an electrical issue. So after tracing wires i found a burnt out wire behind the electric start key. Instead of soldering it back together i threw an old one i had on, just spliced the wires and she started right up. I thank all of you for your input and time. This thing has had me bashing my head for over a week.
Title: Re: Honda motor no spark
Post by: sawguy21 on September 10, 2017, 08:07:38 PM
 8) So you put the smoke back in where it belongs. ;D Glad to hear you are up and running and a little more educated on small motors.
Title: Re: Honda motor no spark
Post by: dgdrls on September 10, 2017, 08:15:28 PM
Glad to hear your back up and running