Chainsaw Repair

How To Basics - Carb Fixes + Mods - IPL and Service Manuals => How To Basics and Fixes => Topic started by: 660magnum on June 02, 2014, 10:09:19 am

Title: SPARK PLUG GAP
Post by: 660magnum on June 02, 2014, 10:09:19 am
Almost all our chainsaws, weed whackers, etc - The spark plug gap is .5mm or .020"

If your ignition is strong enough to jump the gap, the engine will run much better with the spark plug gap set at .025".

Back years ago when you had to change automotive spark plugs all the time and you did a tune up, the engine typically idled better before you tuned it up mainly be cause the new spark plugs had a closer gap.

Running a .025" spark plug gap is something the R/C model airplane guys often do with their gasoline engines because they mostly fly around at partial throttle and they need a reliable slow idle to land.
Title: Re: SPARK PLUG GAP
Post by: KilliansRedLeo on June 02, 2014, 10:29:51 am
Good info Jim, thanks!
Title: Re: SPARK PLUG GAP
Post by: 3000 FPS on June 04, 2014, 12:04:43 am
You know I am glad you brought this up because I have set the gap on my saws for some time now to .025".

I did not know about the idle.    Good info thanks.
Title: Re: SPARK PLUG GAP
Post by: KilliansRedLeo on June 04, 2014, 10:34:42 am
After reading 660's post, I checked a few new Bosch plugs. Found that they were all set to 0.025 right out of the box.
Title: Re: SPARK PLUG GAP
Post by: 3000 FPS on June 04, 2014, 11:54:13 pm
After reading 660's post, I checked a few new Bosch plugs. Found that they were all set to 0.025 right out of the box.

Yes and I have found that NGK and Champion are right at .025" out of the box also.    I change out 4 to 5 plugs on average at work on weed eaters, chainsaws, mantis tillers, leaf blowers, cut off saws, ice augers, and anything else they put a 2 cycle engine on.   I gap them all at .025.