How Do You Change Spark Plugs?

[Zanzer]

As a side note. I have taken up using Fluidfilm for a lot of rust preventative and misc. lubrication applications. i.e. hinges, hood and door latches, etc.

Hope this helps.

Me thinks I have a new product to look into Thanks for the suggestion :thumbup:

I typically use white lithium grease in the spray can but it has a pretty short lifespan in hinges and such and gets nasty with multiple applications. I think I'll be picking up a can of this to try out

[Bert]

This entire post has been both enlightening and amusing. I too am known as a putterer that cleans, inspects, compares and greases every lousy part he takes off. But then again I own cars for the long haul, and my very limited experience (I quit after a month) with working on other cars, where owners didn't give a hoot (ie a 2 hour job turned into 6 because of all the broken, seized bolts and screws), entirely changed my mind about fixing cars for a living.
On the other hand I can forecast that Mr Gunn will never spontaneously attempt to shoehorn a V6 into one of his cars because the preliminary study of spark plug locations (and any number of other details) would derail that process ad infinitum and nothing would ever actually get done.
Gosh darn bless the whole bunch of you folks.

[nitrofarm]

Holy Sha nike ees. Seven pages on a how to change spark plugs. I dont think there will be enough server space for a "How much gap on a Spark Plug"

[Clay]

In that situation I typically break the plugs loose while the engine is cold and then retighten them to "finger tight" (also verify that they screw in and out easily). Then crank the car and let it run until it's at it normal operating temperature (typically a couple of fan cycles). After you shut the engine off you should be able to remove the plugs by just unscrewing them with a socket and extension, no ratchet required since you pre loosened them when the engine was cold.

Personally I would avoid running an engine without the spark plugs properly installed. Maybe remove and reinstall the plugs when the engine is cold, and then warm the engine up and then remove the plugs, and then let everything cool down before putting the plugs back in. It probably does not make a whole lot of difference, but if someone wants to do the math, these should get ya close:

http://hyperphysics.phy-astr.gsu.edu/hbase/tables/thexp.html

http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/thexp.html#c1

I always thought that having the engine hot makes it easier to remove parts. Aluminum expands faster than steel. This means that the diameter of the hole in the head will get bigger more than the plug will get bigger. This also means the the pitch change of the threads in head will be greater than the ones on the plug. It can be a difficult concept to wrap your head around. http://hyperphysics.phy-astr.gsu.edu...thexp2.html#c1

Whether or not to use anti seize is a good question. it does change the affect of torqueing. Maybe if you use OE plugs, use the OE procedure. I would also be concerned about the fact that you are electrically insulating the plug from the head as well as the torque issue.

I always try to change wires and cap and rotor (if equip) at the same time I change my plugs. My first vehicle was a '94 S-10, and it would just quit running sometimes, turns out it was a worn out coil wire.

My mom has a 1998 Honda Shadow 650 motorcycle. It is a twin cylinder and has 2 plugs per cylinder. The manual says to change the plugs every 4 thousand miles. It seems like a ridiculously low interval, but she said she can tell the power difference when they get changed at 4000 miles.

Thought I would toss up some spark plug links:

http://www.ngksparkplugs.com/tech_support/index.asp?mode=nml

http://www.boschsparkplugs.net/faq.asp?pt=1

http://www.youtube.com/watch?v=LbR75wq9nmM&feature=player_embedded

I wonder if anyone reading this thread has a Ford 5.4L and is just laughing at us.

Edit: First Post!!:hello1:

[Safety Guy]

Welcome Clay!

IMO, this thread has been great. Sometimes (when one HAS the time) it is good to "overthink" things.

Karl

[JohnGunn]

As I said these are some things that would interest me. But if there are things you do that aren't on this list, those things would probably interest me even more. I may ask some questions along the way and at the very end reveal what I do in my Zen mode.

This quote comes at the end of my original post that started this thread. Since I have some information that needs to be added I've come back to it and re-read it from start to finish. In spite of some pot holes along the way I am happy that I had something to do with getting the discussion started.

I did change my spark plugs and enjoyed doing it, but, for reasons that are now lost to me, I wasn't able to record the process in the detail I had promised. To try and remember something I did six weeks ago is completely different and much less interesting than a report of those same activities written the day after they were accomplished. For that reason, I'll not bore you with even the attempt at fulfilling my initial promise.

Instead, I'll limit my remarks to those areas which elicited some degree of contention during the time the thread was active, gap size and anti-seize or anti-anti-seize.


Gap Size:

So the first question is, what does it mean when Denso and NGK and even Motorcraft lists the gap of the plugs for our cars as .044"? Here are my thoughts. These manufacturers design their plugs to be used in lots of different models and makes of automobile. That number represents the gap that the plug was designed around. the perfect gap for the dimensions of the plug. For example the ground electrode goes up from the body of the plug and makes a turn to go over the positive electrode. I would say the designers designed the length of the positive electrode and the length and placement of the bend of the ground electrode in such a way that when the ground electrode is exactly perpendicular to the top of the positive electrode the gap will be .044". They chose that as the ideal gap for the geometry of the plug.

What does that mean? Should we favor that number because the surfaces of the electrodes are perfectly parallel at that gap? I think I might.

In the end I decided I would abide by my belief that the best gap is the one that is achieved when the ground electrode is parallel to the top surface of the positive electrode. When I started to gap the Motorcraft, advertised as set at .044", I thought when I set them to the recommended value this parallel relationship would be achieved. That was not even close to true. First, none of them came out of the box correctly gapped. They were all only around .044", not nearly good enough for me.

When I set one of them to .044" using a wire gauge the wire was extremely loose at the first part of the gap and only came down to .044" just as the wire passed over the back-most part of the positive electrode. Just about as far from parallel as you could get at the high end of the gap scale.

That shot to hell my belief that the plug was designed to be parallel at the recommend gap. So what should I do? I decided to remain true to my belief that the electrodes should be parallel to one another. So I adjusted one of the plugs until the edges of the gap between the electrodes were parallel. That turned out to be at about .040", and that is what I set them all to.

Interesting how Zanzer and I appeared to disagree on this at first, only to end up using the same gap, arrived at for different reasons.


To Anti-Seize or Anti-Anti-Seize:

The plugs I chose to use were the plugs recommended by Ford in my car's Owner Guide, AGS32C - a.k.a Motorcraft part number SP-436.

When I bought my Aspire, one of the first things I did was go out and buy a set of NGK Iridium IX plugs. But, before I could install them, I became concerned that the timing belt hadn't been installed correctly and didn't want to put them in until that had been settled. I wanted to wait to install them until I could do so confident I'd not have to take them out over the next 30,000 miles.

I'm still not confident enough of the condition of the engine to want to put them in, so I bought a set of Motocraft plugs to use until things settle down. The NGK plugs are new and expensive so I would expect them to have the nickel plating that prevents seizing, but these Motorcraft plugs bought for $2/each on eBay, are a black color and don't look much like nickel.

Should I follow the consistent advice given by Ford who sold my car and manufactures the plugs, and install the plugs dry, without any lubricant added, or continue a practice that in my mind is of dubious value and could actually do harm?

Id try it without, then every month or so break them loose and retorque them. That way you know they're not seized up.

Thanks for the suggestion, Anomoly40. Instead of wondering what might happen, this way I'll know.

On the subject of using anti-seize I decided to follow anomoly40's suggestion. It would allow me to test for myself whether anti-seize was necessary, helpful, or just an urban myth.

When I installed the plugs I spend a long time cleaning all threads involved, especially those in the holes which had a history of which I was completely ignorant. On those I used a round nylon brush of the appropriate size sprayed with throttle body cleaner which I believe left absolutely no residue.

When I screwed the plugs in they lacked the comfortable feel of well lubricated threads in action, but there was absolutely no resistance to screwing them in. In fact I was surprised at how loose they felt until the washer was reached. In other words, they were completely clean and bone dry.

I torqued them to the lowest value in the range recommended by Ford, 15 ft.lbs.

That was 6 weeks and 1,300 miles ago. Yesterday, I decided to try using Seafoam's Deep Creep to soak the rings of my Aspire, in hopes of improving its power. This required me to remove the spark plugs.

But before I talk about that I must warn you, "Do not to use Deep Creep, or any solvent, for this purpose unless you can be sure when you start your engine after the treatment, that most of the solvent used has been removed from the cylinders. Otherwise you run the risk of hydro locking the engine and doing extreme damage."

I've heard some members say that you can use compressed air to get the soaking fluid out, but since I don't have that available to me along the side of the road where I am forced to work, I bought a two foot length of clear plastic tubing about half the size of the spark plug holes and sucked out all the Deep Creep that I could using my own breath. A suction pump would have been preferred, but if the tube is long enough you can see what is approaching and stop and blow it out before it does you any harm.

That said, back to removal of my un-anti-seized spark plugs. They came out with absolutely no sign of any seizing. I set my torque wrench for 15 ft.lbs and they broke loose before the wrench clicked. I was easily able to unscrew them by hand without any problem. In fact I would say they felt exactly the same coming out as they had going in. When I looked at the threads they were just as clean as they had been when I initially screwed them in. Can I be any clearer about this?

Now, I realize 1,300 miles is not 30,000, but so far it doesn't look good for the anti-seize devotees.

Eventually, I'll have to take these test plugs out at least one more time, when I install those expensive nickel plated NGK Iridium plugs which I would expect to be even less likely to seize. When that happens I promise to come back here to report how that went even if it serves to prove me wrong.

[JohnGunn]

Dry Spark Plug Experiment Update

Please read the anti-seize part of the immediately preceding post to fully understand this one.

Today I checked spark plugs for cylinders 1 and 2. There was no suggestion of seizing in breaking them loose or in removing them. Pictures of the threads are attached. I assume 3 and 4 are just as clean and didn't remove them so that the next removal will show them with a longer time in place without disturbance.

I am satisfied that these basic, black coated, stock Motorcraft plugs are not going to seize, or show any signs of corrosion. The next time they are removed will be when I install the nickel plated NGK Iridium IX plugs I purchased shortly after buying my Aspire, over a year ago.

If these cheaply coated black plugs don't seize, I figure the expensive, nickel plated Iridium plugs won't either. Needless to say, they will be installed au natural. So when that happens, the experiment will end with the report of the condition of all plugs at that time.

I'll try to build a table showing all the operations on these plugs since their installation.

First, the heading for each of the space-separated items:
(Date) (Actual Mileage) (Miles Since Installation) (Which Plugs) (Condition)

15-Jul-2011 82,103 0 All (New and dry, into thoroughly cleaned hole threads.)
26-Aug-2011 83,381 1,278 All (No sign of corrosion.)
22-Sep-2011 83,935 1,832 All (No sign of corrosion.)
13-Jan-2012 86,063 3,960 #1,#2 (No sign of corrosion.)

[Jim Rockford]

a single plug can be used for multiple types of engines, so there is no way they can pre gap a plug at the factory , and expect it to stay gapped during shipping, and still be perfect for every engine it fits, Always gap your plugs and for god sake don't be afraid to dab a little anti-seize on en and put away the torque wrench and just snug em up... its not rocket science

[Movin]

Don't use a click type torque wrench counterclockwise..
it will need its accuracy checked and adjusted if that happens.

[zoom zoom]

a single plug can be used for multiple types of engines, so there is no way they can pre gap a plug at the factory , and expect it to stay gapped during shipping, and still be perfect for every engine it fits, Always gap your plugs and for god sake don't be afraid to dab a little anti-seize on en and put away the torque wrench and just snug em up... its not rocket science

ngk iridiums are pregapped, and shouldn't be re-gapped, the numbers indicate the gap from the factory.

[nitrofarm]

a single plug can be used for multiple types of engines, so there is no way they can pre gap a plug at the factory , and expect it to stay gapped during shipping, and still be perfect for every engine it fits, Always gap your plugs and for god sake don't be afraid to dab a little anti-seize on en and put away the torque wrench and just snug em up... its not rocket science

He doesnt listen to anyone,even Jennifer's Dad.You can beat your head against your Firebird & run Angel over.It wont change his mind. :nono:

[rockin86ranger]

a 20lb sledge hammer, an acetylene torch, and 2 rolls of duct tape (zipties if it needs wires too)

[zoom zoom]

He doesnt listen to anyone,even Jennifer's Dad.You can beat your head against your Firebird & run Angel over.It wont change his mind. :nono:

Whoa, stalkerboy much? Lol, jk, i don't know if you know him or what..

[nitrofarm]

Whoa, stalkerboy much? Lol, jk, i don't know if you know him or what..

Everyone knows JIM ROCKFORD ! Unless your from Marietta?
When you see him he'll be driving a Gold Firebird. And he loves his E Brake!

http://www.hulu.com/watch/34940/the-rockford-files-rattlers-class-of-63#s-p3-so-i0

[tkannegaard]

its just my belief but your not supposed to gap platinum plugs that's why they put the cardboard protector on the threads so if they are dropped in the box lots of copper plugs have this to and all come out at what they were gaped at the factory at