The Forestry Forum

General Forestry => Chainsaws => Topic started by: Beweller on September 06, 2004, 09:35:41 AM

Title: No hot start
Post by: Beweller on September 06, 2004, 09:35:41 AM
I have a Stihl 009 that will not start when hot.  It has been to the shop twice and returned "fixed".  I don't think the shop ever sees the problem.  It occurs only when the saw is hot and has been shut off for more than a few minutes.  Then may be over an hour before it will again start.  Any one encountered this problem?  Thanks
Title: Re: No hot start
Post by: Dean Hylton on September 06, 2004, 12:38:42 PM
What you have is most likely a coil that needs to be replaced. You have a break in the internal wire of the coil. As the coil heats up the gap is widened and you loose spark.
Title: Re: No hot start
Post by: Beweller on September 07, 2004, 10:43:43 AM
Dosen't seem likely.  If the saw is shut down for only a minute it hot restarts OK.  But if for several minutes, then no restart intil it cools.

I have checked and there is a spark during the refractory period.  Maybe weak, I don't know what it is supposed to look like.

Thanks for the suggestion.
Title: Re: No hot start
Post by: Tom on September 07, 2004, 12:32:57 PM
I don't have an answer, but, my Husky 61 will do that every once in a while.  I have always attributed it to a vapor lock.  After about 20 minutes of sitting, it will crank right up.

The only other cranking problem I have had, I found, was a too long fuel line. I had the line replaced along with some other maintenance and found, after turning the air blue a few times, that the filter couldn't "freely move" in the tank.  I shortened it a smidgeon and everything was hunky-dory. ;D :)
Title: Re: No hot start
Post by: Kevin on September 07, 2004, 06:12:15 PM
Does your saw tend to stall out at idle but operate normal at high speed?
You should have a bright blue spark.
Title: Re: No hot start
Post by: Beweller on September 08, 2004, 09:04:04 AM
Runs fine at idle and full throttle.

I would not call the spark I saw hot and blue.  But of course I was looking at it in full daylight.
Title: Re: No hot start
Post by: Beweller on September 14, 2004, 03:46:16 PM
I was pretty sure the trouble had to be some sort of vapor lock.  Only thing I could come up with that seemed to fit all the symptoms.

But because it was easy, I tried replacing the spark plug.  Amazing!  The saw starts fine, hot or cold, including hot after a short rest.

I can't find anything wrong with the old plug.  Huh.

Thanks all.
Title: Re: No hot start
Post by: Minnesota_boy on September 18, 2004, 08:03:32 AM
I worked in a saw shop for a while and that problem with not starting hot was a tough one for the shop man to diagnose.  I had no where to test the saw long enough to get it real hot.  I did find that replacing the plug was a good place to start though.  ;D
Title: Re: No hot start
Post by: sawguy21 on September 20, 2004, 09:49:04 PM
Beweller, was the plug a Champion? I find them very inconsistent. Bosch and NGK are much more reliable
Title: Re: No hot start
Post by: Beweller on September 21, 2004, 07:06:35 PM
The troublesome plug was an Autolite.  I replaced it with a Champion, the only replacement I could find in three stops.

I was trying for the Bosch, but none of the three carried them.

Title: Re: No hot start
Post by: SwampDonkey on September 26, 2004, 01:01:04 PM
The Stihl shop recommends Bosch plugs for their FS450 thinning saw I know.

cheers
Title: Re: No hot start
Post by: james on September 28, 2004, 06:51:22 PM
one verry good way to test for spark is to gold the bare plug wire in your hand and crank the saw ;D ;D
Title: Re: No hot start
Post by: Ianab on September 28, 2004, 08:50:58 PM
Quote
one verry good way to test for spark is to gold the bare plug wire in your hand and crank the saw ;D ;D


I guess that depends on your defination of GOOD  :D
Mine would be to get someone ELSE to hold the plug and crank the saw :D
Title: Re: No hot start
Post by: james on October 02, 2004, 11:14:28 AM
aw, comon lanab -what no sense of adventure? ;D ;D :o :o
james
Title: Re: No hot start
Post by: Timber_Framer on October 02, 2004, 03:06:37 PM
I fouled my plugs on my Harley once in Podunk North Dakota and all I could find that would fit were champions. I didn’t have to replace those plugs for nearly a year, which is unheard of on an old Hog.
If you find a good champion plug they’re as good as any on the market, the problem is as sawguy said finding a good one is sometimes a difficult task.