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Spark Plug Change

Today I did a spark plug change on my car at 16450 miles. I had to order the plugs (Motorcraft Iridium CFSY-12) at my dealer since I was the first mechanic to ask for them. All of the stock plugs read perfect with no signs of running lean or too rich. There is a slight oil film on the threads but electrodes and porcelin were light tan. Some pics of the removed plugs.
Sparkplugs002.jpg
Sparkplugs001.jpg

Easy job, Remove PCV hoses and coil covers, 8mm socket to remove coil hold down screw, 5/8" spark plug socket and 10" of extension. Unbolt coil, pull up a little release tab on harness and pull off wiring, remove coil and clean seals and blow out spark plug well. Remove plug (do with engine cool so you don't pull out aluminum threads) thread in new plug by hand until seated and torque 10 ft/lbs (124 in/lbs). Little dielectric grease in coil boot and push back into well, tighten coil hold down screw to 7 ft/lbs. Replace coil lead (make sure it clicks. Do 8 times and replace covers, and PCV hoses. Test drive and enjoy! Most of you won't be doing this for at least 40000 miles but I like to see what's going on with the engine.
Steve
 
Do you have a wrench that measures that low of torque? I looked for one a while back because I tend to over tighten things but couldn't find anything that I would trust that I could afford. "hand tight" means broken when you have gorilla hands :(
 

steveespo

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The dielectric grease is just a light smear with a Q-tip inside first inch of the boot, sorry no pics. The torque wrench I use for screws and such is a 1/4" drive GearWrench tourqe wrench, measures in inch/lbs, remember in/lbs divided by 12 = ft/lbs. 144 in/lbs=12 ft/lbs.
Steve
 
Nice, I will see where I can get one. Not buying a used torque wrench, had a few go bad on me. Torque on it lines up well with the 20 lb+ one I have.

I needed one of the screwdriver type ones for work a couple years ago, they were $500+. Ended up borrowing one from an electrician.
 
Thanks Steve, couple of thing to add. I would recommend using Anti-Seize (I use Pereatex Anti-seize) brush it on the threads of each plug, just enough to coat it. I started using this on the wheel studs also. Be careful with the tabs on the wiring going into the coil, I was too rough or it was bad to begin with and broke the first one. I did get lucky and had that repaired because of another issue that was warrantied.

Another tool worth using is a long spark plug socket rather then a regular socket and extension. Using one of these reduces the risk of cross-threading.

My plugs were very dirty due the amount of oil being burned. I asked several race teams about oil consumption and they ALL said the 302R is not using any oil. The SM at my dealer plans to show the plugs I removed to his rep, curious to know what they have to say.

CIMG2872.png
 
+1 on the anti-seize. It also helps you get an accurate torque measurement. I use it like 2511 uses Zaino, I put it on ****ing everything. Especially things that get hot. Great for rotor retaining bolts and everything else in the brakes, I have had to drill out a lot of bolts because other people don't use it.

Let us know what they say about the oil, I am at 5 quarts in 2k miles. Only time it didn't burn oil was at the track, didn't burn a drop.
 

steveespo

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I was thinking of anti seize too but I read that Ford does not recommend it on the spark plugs. I looked at the manual and there was no mention so I didn't. I do suggest doing them engine cold so you don't pull the threads out of the head, also a good feel for starting the plug in, if you can't turn them in with two fingers on the extension something's wrong. Only use the ratchet when they are threaded all the way in.
Steve
 

ace72ace

Zaino, I put that $hit on everything
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Don't use anti-seize? Ok, just hit it with a little Z6....................(Zaino) :D
 
I have been using anti-seize for years on engines like the V-10 without issue. Like I said I "recommend" using it, not sure what the official word is but I thought it was recommended by Ford on the old modular motors (same thing with the aluminum heads).
 
I work on commercial aircraft engines,.....you dont use anti- seize upon re-assemble, (specially the hot section) the next guy is going to be cussing you out big time,.... definately by all means use it!
 

Dvendet

Everyone's entitled to my opinion. ;)
All,

Just saw an episode of Motor Week this morning. What do you know, good ole Pat Goss discussed replacing spark plugs in Aluminum heads. Pat indicated something I had not heard before. He recommended that when you first start turning your socket wrench to remove the plug, only turn it one-eighth (1/8) of a turn on each plug. He then said to reconnect the plug, go into the car and start the engine briefly and accelerate the engine quickly "only" one time and then immediately shut down the engine. Now you can remove your plugs. Pat indicated doing this will blow out the carbon in the cylinder that was loosened when you first turned the spark plug. He indicated that doing this will prevent that carbon from working its way up into the threads when you remove the plugs. Pat also indicated two more great tips. First he indicated you should never insert the new plugs with your socket wrench! You should always hand start each plug by hand. Secondly he indicated that for hard to reach plugs that you should attached a small 3-4 inch section of rubber fuel line to the top of new spark plug. Doing this will easily allow you to hand start and turn the plug in hard to reach areas. Sounds like good advice to me.

Other interesting tips he indicated were that he always uses anti-seize on first thread of new plugs when inserting plug into Aluminum heads. Also, when removing a spark plug, if there is any resistance backing out the plug then stop. Then he suggested you slighty tighten the plug and then start loosen the plug again. He said to continue to repeat this process (be gentle) until you have completely removed the plug. Not performing this procedure can easily strip the threads in the head. Never force the removal of the plug!

He also highly recommended all plugs be torqued to manufactuter's torque spec when installing. He stressed this point.

Just thought I pass this info along to all. His tips make a lot of sense and Pat is widely recognized for his mechanical skills and expert advice.

MMD
 
Great writeup Steve. I just finished and am happy to say "no faults" and all cylinders running :-\ If I can do it anybody can :) (Oh and a phone call or 2 to Pete) :-[

Anyway I'd add a couple items to the instructions for novice mechanics like me. First on removing the coil plug. If you take a small flat screwdriver and insert it under the tab to release as shown in the pic below, the coil plug will slide right off. I also removed the strut tower brace and the battery connections by cylinder 4 to get better access.

Plugs looked similar to Steve's. Look ok? Figure I'll throw them in the trailer as spares.
 

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