HOW TO: Change Spark-Plugs

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tommudd

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NOW back to why we all will tell you what works best is the fact we do try and help each other and new owners, be it lifts, tires, or spark plugs. This motor was designed around a copper plug, its what works best and they are cheap and easy to change. Its not that anyone is trying to be a jerk, its just what works best.
many of us have been around since almost the beginning of the KJs ( and lots of Jeeps before that even) if something like the iridium's worked better we'd be using them, BUT THEY DO NOT!
 

CalcityRenegade

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When I first bought my KJ I decided to replace the spark plugs and when I grabbed some at the part store the kid gave me Iridium plugs. I did not know the difference at the time and the old guy working the till saw them and asked me "What idiot gave you those". He promptly went into the back and grabbed me copper cores.
 

mohamer

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tommudd,
I appreciate some of your comments.
Maybe you should do more of a search for information than just Carsdirect.com,
Your comments are a direct quote from them.

"Advance Essentials: Spark Plugs Basics


Spark plugs Spark plugs

It’s time to tune up your car, so you head to the Advance Auto Parts website. Once there, you enter the year, make, model and engine size of your vehicle. You want to buy the best spark plugs so you click on “spark plugs” and up come more choices than you expected. In most cases, you’ll see at least four different types of spark plugs, from at least three different manufacturers. Will it be platinum spark plugs? Copper spark plugs? Iridium spark plugs? How do you know which are the best spark plugs to buy? Simple. Just pick the spark plug based on the type of ignition system in your vehicle. Here, we’ll further explain the differences between platinum spark plugs, copper spark plugs, iridium spark plugs and other spark plug types. Plus we’ll give you some solid advice on which are the best spark plugs for your vehicle.

Let’s start with the two most important spark plug facts. First, sparks like to jump from the sharpest point on the center electrode to the sharpest point on the side electrode. So you want a plug that retains its sharp edge for the most miles. Precious metals like platinum and iridium are harder and have lower melting temperatures than the nickel alloy electrodes found in traditional copper spark plugs. Second, the smaller the diameter of the center electrode, the lower the voltage needed to start the spark. Keep those shopping tips in mind as you review the best spark plugs for your vehicle.

Copper spark plugs—where to use them
Copper Spark plugs Copper Spark plugs

Copper spark plugs have a solid copper core, but the business end of the center electrode is actually a 2.5mm-diameter nickel alloy. That’s the largest diameter electrode of all the spark plug types. Remember, the smaller the diameter, the less voltage required to initiate the spark. Nickel alloy is also softer than either platinum or iridium, so the sharp firing edge you get right out of the box tends to wear out quickly. Despite those shortcomings, copper spark plugs are still a good choice for certain applications. Copper spark plugs are best for older (pre-‘80s) vehicles with low voltage distributor-based ignition systems. But don’t use copper spark plugs in high-energy distributor-less ignition systems (DIS) or coil-on-plug (COP) ignition systems. They’ll wear out too quickly.
There’s one exception to that advice. Some late-model high-performance engines were designed specifically for copper spark plugs. In those cases, copper spark plugs are considered to be high performance spark plugs. If your owner’s manual calls for copper spark plugs, don’t upgrade to platinum spark plugs or iridium spark plugs. Single platinum spark plugs—a step up from copper spark plugs
Single platinum spark plug Single platinum spark plug

A single platinum spark plug is basically styled after a copper spark plug with a platinum disc welded to the tip of the center electrode (see photo). Since platinum is harder than nickel alloy, it holds its sharp edge for as long as 100,000 miles. Platinum spark plugs also run a bit hotter, preventing spark plug deposit build-up and fouling.
Platinum spark plugs are usually the best spark plugs for newer vehicles with electronic distributor-based ignition systems and some (DIS) systems. If your owner’s manual recommends platinum spark plugs, don’t downgrade to copper spark plugs to save money. However, you can upgrade to either double platinum spark plugs or iridium spark plugs.Double platinum spark plugs—twice as good?
Double platinum spark plugs Double platinum spark plugs

Double platinum spark plugs were designed for “waste spark” DIS ignition systems. In a waste spark system, the spark jumps from the center electrode to the side electrode for the cylinder that’s on the compression stroke. To return the electrical pulse back to the ignition coil pack, the spark jumps backwards (side-to-center) on the partner cylinder. Since the partner cylinder is on its exhaust stroke, nothing ignites and the spark is “wasted.” You can’t use single platinum spark plugs or traditional copper spark plugs in these systems because the side electrodes aren’t designed to handle the reverse spark. But double platinum spark plugs, with a platinum disc welded to their side electrode, work exceptionally well. Both the center and side platinum discs remain sharp, allowing sparks to fly easily in both directions without causing rapid electrode wear.
If your owner’s manual recommends double platinum spark plugs, then those are the best spark plugs to use. Never downgrade to single platinum spark plugs or copper spark plugs. However, you can upgrade to an iridium/platinum combination plug (an iridium center electrode with a platinum-tipped side electrode).
Double platinum spark plugs


On the compression stroke
The spark shoots from the center electrode to the side electrode


Double platinum spark plugs

On the partner cylinder exhaust stroke
The spark shoots from the side electrode to the center electrode — why double platinum spark plugs are needed in a waste spark DIS system




Iridium spark plugs—the best kind around
Iridium spark plugs Iridium Spark plugs

You guessed it: iridium is harder than platinum. In most cases, iridium spark plugs last about 25 percent longer than comparable platinum spark plugs. Because iridium is costly, iridium spark plug manufacturers reduce the diameter of the center electrode to as little as .4mm. In addition to saving money, the “fine wire” center electrode of iridium spark plugs increases firing efficiency.
Many carmakers require iridium spark plugs or iridium/platinum combination spark plugs for (COP) ignition systems. If your owner’s manual specifies iridium spark plugs, don’t downgrade to platinum spark plugs, or double platinum spark plugs, or even copper spark plugs. They won’t perform as well as the iridium spark plugs in this case."

I quoted that from Advanceautoparts.com
It is quite educational.

As a moderator you should not put down certain populations just because of the car they may own, that is a very backward thing to do.


Thanks,
John in Joplin kb0ou ;)
 
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tommudd

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I quoted that from Advanceautoparts.com
It is quite educational.

As a moderator you should not put down certain populations just because of the car they may own, that is a very backward thing to do.


Thanks,
John in Joplin kb0ou ;)[/QUOTE]

I would never quote from Advance Auto either since the only good thing I have ever found from them was car wax
I never downed anyone , never did I say anything bad about another car or owner, don't care what you drive BUT after working on / in and around various vehicles my whole life I do know something about what works and what doesn't
AGAIN Mr. John only trying to help
but...........as Grandpa always told me , well ............:shrug::happy175:
 

ouroboros

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If your owner’s manual calls for copper spark plugs, don’t upgrade to platinum spark plugs or iridium spark plugs.


Can I just make a point here that if you open the hood of your KJ, it will tell you SPECIFICALLY the make, model and brand spark plug they want you to use in that motor. So, maybe we should take that into consideration here. Even my parts books at work pop up with the OE recommended plugs being NGK R copper cores. Pretty sure the measly, under-paid and uneducated Chrysler engineers just completely goofed that one up though, right? :happy175: Argue all you want, either way the answer is pretty obvious, just pop your hood! :icon_lol:
 

mohamer

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Oem

Howdy,
Yep, I popped my hood, Jeep is so cheap that they put the cheapest plugs they can get the lowest bid on in the engine from the factory and you think that is what I must run.... :shrug:

How many of you guys run OEM tires on ur Jeep? I think ya might try something different for a change. How about gasoline, does the stuff u pumped in last time meet the exact specifications of the gasoline they put in at the factory??

How about oil, I use 5/30 synthetic in my Jeep, WIX oil filter, are those OEM. Air Filters, surely U would not run K&N!!!..;(

Oh, tommudd, I saw some of ur posts on jeepforum.com,, Mr Autolite and you disagree,, You might open ur brain just a little bit guy!!! ;)

Ya gotta get out of the box guys!!!

By the way, not a miss with the IX plugs in the 3.7L Jeep engine, runs great!!

Like they used to say at Phillips 66,, It is PERFORMANCE that counts!!!:gr_grin:

Thanks again for the original post on how to change the plugs...:icon_lol:

John in Joplin kb0ou :happy175:
 
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tommudd

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You talk about people attacking you, yet every chance you get you attack them in some way
Interesting for sure
BUT Out of curiosity I called my buddy last night to discuss spark plugs, he agreed that the copper NGK/ Champions were the best as well for the 3.7 the Iridiums he said he pulls and tosses everyday that other garages install for more $$$. He has his own small shop now.
OH his background, ............
he worked for Champion Spark plug company for over 34 years. His job was to find the right plug for the various engines. Last 12 years was spent as the lead down in Florida doing marine engines only. Great guy and a wealth of knowledge.
 

ouroboros

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You talk about people attacking you, yet every chance you get you attack them in some way
Interesting for sure
BUT Out of curiosity I called my buddy last night to discuss spark plugs, he agreed that the copper NGK/ Champions were the best as well for the 3.7 the Iridiums he said he pulls and tosses everyday that other garages install for more $$$. He has his own small shop now.
OH his background, ............
he worked for Champion Spark plug company for over 34 years. His job was to find the right plug for the various engines. Last 12 years was spent as the lead down in Florida doing marine engines only. Great guy and a wealth of knowledge.

You know Tomm, we should probably just be laughing at the fact that the poor guy got swindled into some laser iridium plugs with a fancy description about how they have "high performance" and "great fuel efficiency" :happy175: Oh yea, that 100,000 mile guarantee:laughing1:
 

tommudd

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You know Tomm, we should probably just be laughing at the fact that the poor guy got swindled into some laser iridium plugs with a fancy description about how they have "high performance" and "great fuel efficiency" :happy175: Oh yea, that 100,000 mile guarantee:laughing1:

I know right?
But to each his own, that's why there is white bread and wheat etc
I know from experience, researching etc what works for me the best
 

ouroboros

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I know right?
But to each his own, that's why there is white bread and wheat etc
I know from experience, researching etc what works for me the best

Can only live and let live. Maybe one day the KJ gods will smite us for not using them fancy spark plugs. :shrug:
 

dude1116

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I quoted that from Advanceautoparts.com
It is quite educational.
Thanks,
John in Joplin kb0ou ;)

OK. Now I'm going to be mean. You're REALLY freaking dumb. Idiotic actually. The kid that is given the answers on the test and will argue 'til he's blue in the face that his wrong answer is correct.

Please. If you don't like this board or these people, leave. I encourage it!
 

mohamer

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Good to Know

Hey tommudd,
It is good to know someone like that, an expert.
If you want to change those plugs every 25,000-30,000 miles, more power to ya. Obviously those copper plugs I took out of my Jeep had not been changed for some time. I think I will stay with the IX plugs, I have run with them in motorcycles for about 200,000 miles and not had a problem and hey, the Jeep is actually made for them as it is COP system, just made for them. IMHO YMWV

I will repeat from my original post, thanks to the forum for information that made my Spark Plug change a little easier. All this crap about the IX plugs and MY owning a Prius is just a bunch of BS, you as a moderator should know better.

I also got help from a post about brakes, I needed to adjust my parking brake, it is now more better. Thanks Again.

Don't wear those threads out on yer heads changin all those plugs!! :emotions34:

Have fun... John in Joplin kb0ou :happy175:
 

tommudd

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Hey tommudd,
It is good to know someone like that, an expert.
If you want to change those plugs every 25,000-30,000 miles, more power to ya. Obviously those copper plugs I took out of my Jeep had not been changed for some time. I think I will stay with the IX plugs, I have run with them in motorcycles for about 200,000 miles and not had a problem and hey, the Jeep is actually made for them as it is COP system, just made for them. IMHO YMWV

I will repeat from my original post, thanks to the forum for information that made my Spark Plug change a little easier. All this crap about the IX plugs and MY owning a Prius is just a bunch of BS, you as a moderator should know better.

I also got help from a post about brakes, I needed to adjust my parking brake, it is now more better. Thanks Again.

Don't wear those threads out on yer heads changin all those plugs!! :emotions34:

Have fun... John in Joplin kb0ou :happy175:

Attacking me again, when I said I didn't care what anyone drove,
I don't care what you drive
I don't care what spark plugs you use
I don't care where you buy your clothes
or how you blow your nose
What I do care about is helping people who need help
So now I am out of this conversation
Have a wonderful day
I know I am :mexsmoke:
 

mohamer

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Mr. Idiot to You

Wow,
Mr. D, Leave, I don't think so, I still have to drive you sane.
Freaking dumb, why don't you say the words you mean, sir.
Idiotic, how immature. I put IX spark plugs in a system just made for them and put a note of THANKS on the forum and these are the comments I get from nice forum members!
And Mr. T, a forum Moderator, Attack, I don't think so.

I just got back from a trip to Big Bend, TX. The Jeep performed very well indeed, those spark plugs never missed a beat. A lot of off road travel, and on road travel and I still got right at 20 mpg with the lovely little Jeep.

Again I say, Thank You, to all the forum members for posting all the help to me and all the others that have used it to do projects on the KJ Jeep.

Agree with me or not on the use of Iridium Spark Plugs or with my wife driving a Pruis, that is up to you. I will stick with Iridium Spark Plugs and the Prius is still a good high fuel mileage vehicle. And I will agree to disagree with Mr. dude1116 and Mr. tommudd. I do not plan to leave the forum, I just joined it and will probably stick around a while.

Again, thanks for all the valuable posts on this forum.

John in Joplin kb0ou :gr_grin:
 

mohamer

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Good Advise

So kick back/ relax and enjoy the party :mexsmoke:

Thank You Mr. T :gr_grin:

I believe I shall.... :icon_lol:


John in Joplin kb0ou
 

CalcityRenegade

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Not trying to stoke the fire here but just wanted to mention something. My brother girlfriend has a 2002 KJ Sport and had her spark plugs changed to the fancy overpriced ones and had nothing but issues. Misfires. Rough idle ect. Ensured they were gapped proper and seating correct and the same issues. Took them back and got Champion Copper Cores. Runs great without issues. Kind of found that interesting.
 

sunrisew

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I know this is an ancient thread and the original poster may not even be on the board anymore, but thank you to everyone who contributed to this conversation. It gave me the confidence to change out the plugs myself on the '05 Liberty I recently acquired. It has 125K miles, and I think they may have been the original plugs, so I'm trying to provide some TLC and get this vehicle back to peak performance (or as close to that as possible).

Per earlier conversations, I went with the Autolite Double Platinums and they seem to be running as smooth as silk. I did find it easier to remove the air intake hose. I also moved the coolant reservoir by removing the two nuts that connect it to the bolts on the firewall. After doing that, it lifts out a few inches, and the hoses can be carefully directed so you can place it a few inches to the left. I found this made it much easier to access the two rear passenger-side plugs, and with a couple of extensions, I was able to make turns without potentially damaging the dipsticks as also discussed somewhere above.
 

tommudd

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I know this is an ancient thread and the original poster may not even be on the board anymore, but thank you to everyone who contributed to this conversation. It gave me the confidence to change out the plugs myself on the '05 Liberty I recently acquired. It has 125K miles, and I think they may have been the original plugs, so I'm trying to provide some TLC and get this vehicle back to peak performance (or as close to that as possible).

Per earlier conversations, I went with the Autolite Double Platinums and they seem to be running as smooth as silk. I did find it easier to remove the air intake hose. I also moved the coolant reservoir by removing the two nuts that connect it to the bolts on the firewall. After doing that, it lifts out a few inches, and the hoses can be carefully directed so you can place it a few inches to the left. I found this made it much easier to access the two rear passenger-side plugs, and with a couple of extensions, I was able to make turns without potentially damaging the dipsticks as also discussed somewhere above.

No on the double plats, plain copper core NGK or Champions, but now that you know how it will be easy in a few thousand miles
 

sunrisew

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Yeah, I guess I screwed up on the plugs because all the posts on this and other boards from 10 years ago (and I mean a LOT of them) were saying the Autolite Double Platinums were the consensus choice. I did not notice the last five pages of this thread until after I did the job (my browser was being funky and didn't show me there were more than nine pages of posts). So, now I've read the heated argument where everyone says I need to stick with the copper core OEM plugs (except for the one guy in Joplin). I guess I'm glad I did not accept the advice of the guy at O'Reilly Auto Parts who tried to up-sell me to the iridium. I've only put about 10 miles on the vehicle since the change, but it is running as smooth as possible. I did notice a really bad odor coming from the exhaust emissions that I don't recall being there before. Are there any particular signs for which I should be watching that would indicate I am having problems directly related to the plugs? I read your comments about heat. Do you know of cases where the coils or heads were damaged because of the higher heat from the platinum plugs? Is this a big enough deal that I should redo the job in the opinion of the veterans here, or is it more that this was merely not the best choice, and if I don't have issues I am fine waiting to switch to the copper in 30K miles?
 

Dave

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Yeah, I guess I screwed up on the plugs because all the posts on this and other boards from 10 years ago (and I mean a LOT of them) were saying the Autolite Double Platinums were the consensus choice. I did not notice the last five pages of this thread until after I did the job (my browser was being funky and didn't show me there were more than nine pages of posts). So, now I've read the heated argument where everyone says I need to stick with the copper core OEM plugs (except for the one guy in Joplin). I guess I'm glad I did not accept the advice of the guy at O'Reilly Auto Parts who tried to up-sell me to the iridium. I've only put about 10 miles on the vehicle since the change, but it is running as smooth as possible. I did notice a really bad odor coming from the exhaust emissions that I don't recall being there before. Are there any particular signs for which I should be watching that would indicate I am having problems directly related to the plugs? I read your comments about heat. Do you know of cases where the coils or heads were damaged because of the higher heat from the platinum plugs? Is this a big enough deal that I should redo the job in the opinion of the veterans here, or is it more that this was merely not the best choice, and if I don't have issues I am fine waiting to switch to the copper in 30K miles?


My opinion highlighted.


Dave
 

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