Chainsaw plug life!

[pleasant]

How long should a chainsaw plug last and/or when do you know its time for changing?

 

Plugs can last anywhere between 5 minutes and 5 years+

 

There is no hard and fast rule, and like someone has already mentioned if it aint broke etc etc.

[Andrew Reed]

 

But if there is any problem at all engine wise i.e. not idling, difficult to start, then first thing to do is replace the spark plug.

 

yep, I would agree with comments above as well. Trouble starting, then change the plug anyway. It that does not fix it then you know it is something else and not the plug. I would not clean a plug with wirebrush. If accidently oiled up or fuel flooded, then wash with a paint brush in petrol, clean and dry with a rag, and blow off. If hard fouled, then simply change it (and work out why it was fouled in the first place). Plugs are not expensive compared to time spend fiddling about with other things on small engines, including time spent trying to clean and insulator with a cocktail stick and a scrap of emery paper.

 

But I have noticed that plugs can last for many many years of service without any trouble (two stroke and four stroke) . I would be interested if anyone technical here knows for sure what actually ages and breaks down on a spark plug. Based on some work I did years ago on inspecting sparking plugs in a spark plug tester pressure chamber, I'll guess the insulator surface becomes deposite coated, it then sparks partly and occassionally accross the insulator, which weakens the main spark at the tip. Maybe that would show itself as a weak spark for starting and misfires under load.

Edited January 24, 2012 by Andrew Reed
typo

[spudulike]

Only ever seen one plug that came out of a saw that needed changing - worn electrodes - they normally last for many years!

[Stubby]

NGK I find are the best for reliability and long life. Bosh are not bad but the ones badged Oregon are pants . I have an 02 Husqvarna 357 and I think its on the same plug as was in it when I got it . Although lots of people on here have said don't do it - - I have wire brushed it up a few times and re set the gap . Ho hum

[blazer]

often with any type of HV insulators, they will 'track' and burn a carbonized track to short/cct. Yrs ago at tech they had a plug tester that put a pressure under the plug, so you could see it fail.

[GardenKit]

Due to the nature of my work, i.e. charged for services, I obviously always change the plug on a service. I will only use NGK .

 

It does however seem a little wasteful to bin around 1000 plugs a year, maybe I'll bag them up in 20's and sell them on flebay!

[blazer]

good idea - I keep say 10 in a plastic ammo box (HMR) for wet plug days:thumbup1:

 

Always remember my dad saying he changed the plugs (cheap ones) in his pre-war car but it ran rough, his mate found x4 rusty plugs on his scrap heap, wire brushed them and fitted them, the old car ran well - taught me never buy cheap plugs:sneaky2:

[chainsawMal]

Check HT leads in the dark, old car trick is to run the engine in the dark and look for HT leakage.

 

So what does it look like?