Spark plug

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MoDoug

Minister of Fire
Feb 3, 2018
583
NE Missouri
I have a Stihl 025 that specs call for a Champion RCJ6Y spark plug. I know there are other better brands, but that is what I have in my saw, and I have a new Champion RCJ8Y on hand. The 8Y plug burns a little hotter than the 6Y, other than that all else is the same. Would I be ok running with the 8Y plug or will it be too hot, possibly causing damage?
 
Will it run fine? Probably

Could it possibly detonate causing piston damage from too high a heat plug? Possibly

IMO buy the correct plug, saving a couple bucks isn't worth the headache if something goes wrong.
 
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Are you having troubles? Why change it at all?

It really is running pretty good, although some times it takes more cranks than it normally does and takes a couple squeezes of the trigger to smooth it out when first started. I have the spark plug on hand and thought I would see if it makes a difference. Not sure if trying a different plug running a little hotter is a good way to test it out.
 
Will it run fine? Probably

Could it possibly detonate causing piston damage from too high a heat plug? Possibly

IMO buy the correct plug, saving a couple bucks isn't worth the headache if something goes wrong.

That's in the back of my mind also, which is why I'm asking. This Stihl was my dads and is still running strong.
 
Personally, I would leave it the way it is. Its not like a car that shows some improvement with new plugs. If its starting fine and idling decent, all is well in my books.
 
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Personally, I would leave it the way it is. Its not like a car that shows some improvement with new plugs. If its starting fine and idling decent, all is well in my books.

That's what I'll do, and order a new proper plug to have on hand. Appreciate all the comments.
 
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Add Seafoam to your gas mixture
That will probably take care of the issues described.
 
Yes Seafoam
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Add Seafoam to your gas mixture
That will probably take care of the issues described.
I'm pretty sure I have some on hand, I'll have to do this. I do use high octane, no ethanol gas in my small engines and boats.
 
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Millions of spark plugs senselessly die a premature death at small engine, and especially auto repair shops every year.
 
Don’t wanna totally derail this, but here we go..... what is sea foams purpose? I have a hard time believing claims. Cleans intake and exhaust valves, cures idle problems, grows hair back etc.
When and how are you guys using this stuff. Is it because your fathers used it. Like marvel mystery oil.
Also I don’t think I’ve ever changed a plug in a small engine and noticed a difference. The exception is two stroke dirt bikes. Maybe bc I’m not using sea foam along with new plugs.
 
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It's the new mystery oil, pour some in your gas tank and run the machine normally .. that's it.. do it once in a while .. ==c
 
Don’t wanna totally derail this, but here we go..... what is sea foams purpose? I have a hard time believing claims. Cleans intake and exhaust valves, cures idle problems, grows hair back etc.
When and how are you guys using this stuff
The bottle might be full of exaggerated BS. It’s basically a versatile solvent that breaks down carbon and gunk but also has good lubrication properties. So it’s fairly safe to use and blends with oil/gas/diesel and doesn’t leave residue. Works nice to soak little parts like carburetor jets and screws, and for brushing carbon off. I suppose if you always used it that maybe you’d see all their claims but it’d be $$.
I put it in rarely used stuff like my push mower, wood chipper, and log splitter that might get some condensation or gunk after sitting. A little Seafoam in the tank seems to break down light gunk for me. Saves having to pull apart little carbs and ripping gaskets, etc. I just keep a bottle around.
Despite the claims shown on the gas pumps, I think today’s gas and diesel suck for motors and doesn’t last long.
 
That's what I use it for. Before pulling a carb I add seafoam and let it sit overnight. It often works.
 
That's what I use it for. Before pulling a carb I add seafoam and let it sit overnight. It often works.

I've got an atv that's leaking gas, probably the carb. I need to try this, but I'll probably buy a new carb, they're reasonably cheap and I really don't feel like tearing a carb apart.
 
I saw it work wonders on a old quad that had been sitting for 12 years...
I put that sh!t in everything now.Just added a can to my pickup that was running like crap with a check engine light on.200+ mile trip it's back to normal and the light is gone for a year or so.
 
And you can now run faster, jump higher too!!