Standard spark plugs vs. iridium.........

[Scrubcadet10]

a lot of NGK fakers out there. go to a local auto part store that carries NGK etc

 

[gamma_ray]

I have a Scag Liberty 48" with the Kawasaki FR651V. All is well in terms how it runs, but at some point will change the spark plugs. Do the iridium plugs have enough benefits to justify the higher cost?

I don't think so. As easy as mower plugs are to change, go with standard ones.

 

[SamB]

Your spark plug isn't better than my spark plug because the T.V. says so...

My spark plug(s) are better than your's because I draw little smiley faces in the insulators! So there! :-D

 

[bertsmobile1]

I'd say iridium are for sure "better" technically and they will last longer assuming you have no negative factors affecting the plugs like overheating or fouling. With that said - will you EVER realize any real benefits to justify the costs? Probably not.

Our airplane has a 5.9 liter 6 cylinder air cooled engine making 200hp turning 2700 rpm with dual spark plugs and dual independent magneto fixed timing ignition. Fairly similar to a mower engine in hp per liter and RPM. We run iridium plugs in it because of significantly longer plug life, slightly better low idle smoothness (maybe), easier starting (maybe), and reduced maintenance because the electrodes for them are smaller and re-gapping isn't required. Regular copper plugs last ~400 hours in an aircraft engine, and iridium plugs (also known as "fine wires") can last up to 2000 hours. It's worth it on the aircraft despite some absolutely eye watering prices.

I wouldn't bother on a lawn mower engine though despite the technology being superior. It just doesn't practically make a big enough difference and swapping a plug on a mower every 250 - 500 hours and takes all of 2 minutes and will probably never save you money or hassle.

Yes it's better, no you probably don't need or want it.

but does you lawnmower run under lean burn conditions at 30,000 feet ?
Is your mower running on 100 octane avgas ?
FWIW I probably pull around 200 plugs a year out of engines and of these 200 plugs 190 would get the plug gap adjusted & replaced
The only time a plug actually needs to be replaced is if it is damaged or worn out
Worn out is when the center electrode is level with the insulator nose or the insulator has started to crack & break up from the effect of thermal cycling
Got dozens of customers with engines still running the same plugs as they were when I first saw them 9 years ago and for may of them that is better than 1000 hours ago.
Then again my aim in business is to have happy customers not to fleece them for every last cent that can be justified .

 

[bertsmobile1]

My spark plugs suck, Why do they put resistor plugs on mowers? I'v had 6 mowers with bad plugs this month. Mostly NGK r

You have problems with either your fuel quality or with your ignition.
No plug brand is significantly better than any other in the same price grouping.
Every plug that comes off the machine is subjected to a variety of tests and sorted out according to the results
Top quality goes into individual boxes
Lowest quality goes into supermarket blister packs with a house name printed on the side .
Because of our friends in California, the maximum lever of lead acceptable in exhaust is < 0.00001 %
At that level the 1 molecule of lead that is liberated from the glaze on the insulator nose per hour will push the emissions over the limit, despite the fact that it is part of the glaze and so strongly attached to it that you would need a volcano to seperate the lead from the porclean.
So the noses are not glazed
In order to make higher profits the oil companies blend "fuel" which is NOT PETROL out of all sorts of otherwise unuseable volatile liquids .
Now old real petrol did not conduct electricity untill it made a thick continious film on the plug combine with free carbon.
Modern fuel vapour is highly conductive at cylinder compression
So if the engine does not fire right up then the "fuel" deposits a fine film of conductive material all over the plug and because the nose is not glazed it stays there so you end up with a leakage palth down the insulator of lower resistance than the gap so that is where the electricity goes.

HAving said that any one who buys anything from Ebay or Amazon where you never actually know who the actual vendor is are begging to be ripped off by criminals selling counterfeit goods or genuine parts that were supposed to be sent for scrap recovery but got diverted by a middle man to be sold to cheapskates.
Hundreds of real stores you can walk into & buy genuine spark plugs from a real person

 

[upupandaway]

My spark plug(s) are better than your's because I draw little smiley faces in the insulators! So there!

I draw lightning on mine. I swear my riding mower cut quicker when i painted flames on the sides.../s

 

[txmowman]

It's a lawn mower engine. Iridium plugs will make no difference, same as using premium fuel will make no difference. But, it's your $$

 

[SamB]

I draw lightning on mine. I swear my riding mower cut quicker when i painted flames on the sides.../s

Dang! Bested again! Lightning AND flames!?
(I don't suppose flame DECALS would be better than PAINTED ones, would they?)

 

[slomo]

Standard copper plugs with no resistor if you can snag them. No need to reinvent the wheel.

 

[aussielawny]

It's a lawn mower engine. Iridium plugs will make no difference, same as using premium fuel will make no difference. But, it's your $$

This ^^