spark plug removal - best practice?

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Hi all:

I plan on removing the original spark plugs on my 95 Maxima. The service requirement is 60k and no mileage stipulation but I'm over the 60k now.

Since the car has aluminum heads, I certainly don't want to do damage and have done a ton of reading on spark plug removal protocols. Folks advise using penetrating oil the minute you encounter any squeaking or resistance followed by sequential CW and CCW motion to slowly back it out, but would it be wise to loosen the spark plugs just a 1/4 turn or so and then place a few drops of something like PB Blaster and let it sit overnight as a precaution before going further? I was thinking of doing this even before loosening the plugs but got to thinking it probably wouldn't get past the seated gaskets of the plugs.

Also I came across an interesting video sponsored by Motor Week where Pat Goss suggests something interesting I wanted to run by the forum. He says it is a good idea after cracking the spark plugs to actually start the engine and rev it in order to blow off loosened carbon on the bottom threads of the spark plug (presumably through the exhaust valve?) so it doesn't get pulled into the threads as you remove the rest of the spark plug. Has anyone heard of this?
https://www.youtube.com/watch?v=RKxf0Rl2Pls

Finally, NGK told me that if I use penetrating oil, after the spark plugs are completely removed, to crank the engine in order to blow out any oil that has dripped into the cylinder. I would think it would burn off but then again I suppose they suggest this so it doesn't immediately foul the plug? They didn't seem concerned about penetrating oil actually remaining on the threads of the spark plug hole.
 
If heating the engine up doesn't help and you need to use a penetrating oil, you don't need to fill the entire bore. Just a few ml to cover the bottom around the plug. Any penetrating (mineral) oil that makes it's way into the combustion chamber will burn off. Your engine isn't going to hydrolock with that small amount. In fact it might be beneficial, WD-40 for example is commonly used to clean carbon from piston tops.

If you're worried about the threads, buy a thread chaser. They're not expensive.

Before I pull the plugs I suck out the bore hole with my shop vac. I tighten to spec... luckily I've never had a plug back out like some have experienced. Use a little dielectric grease and call it a day.
 
Try one first. There is no sense in over thinking this right off the bat, because chances are they'll come right out. Try the one that's easiest to get at first. As always don't force anything.

One thing I always do after I pull all of the boots off, (which can often be more difficult than getting the plugs themselves out), is to blow off the depressed area of the head around the plug itself. In 60,000 miles of driving dirt, and even small pebbles, grains of sand, etc. can accumulate in these depressions, and fall into the cylinder when you remove the plug.

By blowing them out with a air gun, and a good shot of compressed air before hand, you eliminate that possibility. Once you get them out, I would for sure and for certain apply a good even coating of anti seize on the threads of the new one's before installing them. I don't care what make they are. I like to run them in and out a couple of times to evenly distribute the anti seize along all of the threads. Aluminum heads usually have a LOT of thread surface engaging the plug.

I usually stick a piece of 1/4" or 5/16" I.D. fuel line hose over the plug insulator to do this. It makes it easier than trying to fumble around with 2 fingers. And a lot of these plugs don't stick far enough out of the head, to offer you any kind of grip on them. The fuel line hose trick makes it a lot easier and faster getting them in and out.
 
I blow out the sparkplug recess with compressed air using a small diameter air gun. Next, use a crossover from your spark plug socket to go to the next highest size ratchet wrench. You are going to need plenty of torque. Give it left hand torque until the plug unseats. It may squeal. Give it a shot of liquid wrench or equivalent. Go for coffee. Come back and finish the job.
 
Well, I've done stone cold removal with the aluminum and I asked my pal who teaches the new GM techs and that's what they teach.
 
Originally Posted by Lapham3
Well, I've done stone cold removal with the aluminum and I asked my pal who teaches the new GM techs and that's what they teach.


Same here, easy peasy
 
I may be wrong, but... some of my best learnings are from old shool mechanics.

Penetrating oil- Most if not all spark plugs have crush washers..their purpose is to crush and seal against the head and plug. Then there is the seal by the many threads that most if not all spark plugs have. I was told that if 1000psi of combustion pressure cant bypass those seals..that penetrating oil wont.

The hardest spark plug that i have seen to remove was broken due to force.. an ice cube was used on the remaining plug and it came out.
 
Originally Posted by Bailes1992
Get the engine red hot before removal.


You're kidding right? That's the worst advice I've heard on this forum yet. A sure recipe for striping the threads.
 
Buy something with inline cylinders to start. Stone cold engine. Patience, don't put them in too tight, 1/4 turn past snug , just like a spin on oil filter or a drain plug
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NEVER remove plugs when the engine is even warm. You want ambient temperatures. My experience is not getting them loose, it's actually making sure the plug socket fits securely on the plug before you even begin to loosen. If not, you can round off the plug edges and then you got problems. I always drop the socket with an extension on to the plug and make sure it's on there nice and tight, then hook up ratchet and slowly remove them.
 
Originally Posted by Skippy722
Originally Posted by Lapham3
Well, I've done stone cold removal with the aluminum and I asked my pal who teaches the new GM techs and that's what they teach.


Same here, easy peasy

Me too. I just make sure the recess where the plug resides is blown out with the air compressor first.
 
Originally Posted by NissanMaxima
...but would it be wise to loosen the spark plugs just a 1/4 turn or so and then place a few drops of something like PB Blaster and let it sit overnight as a precaution before going further?

If you get them to go a 1/4 turn out, I think you're good to go. Keep going at that point.
 
Thanks for all the great quick replies although, I will be doing this on a cold engine.

I definitely know about blowing out debris and have a nice can of compressed air ready.

But what about that video from Motor Week and Pat Goss (linked in my first post) saying you should start backing them out and then start the engine to presumably blow out any loosened carbon that would otherwise pull up into the threads when you continue to remove the plug?

And, do folks think cranking the engine after they are all removed to blow out penetrating oil (as NGK suggested) is unnecessary?
 
The good news is that your Maxima has cutouts in the intake, so it's easy to access the rear spark plugs
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I have a 96 I30. I just removed the old plugs and put new ones in. I used Denso iridium and no anti-seize. I didn't do any special prep for the job, just did it first thing in the morning with a cold engine. I did use a torque wrench when installing the new ones.

Cranking the engine like you describe is not necessary
 
A old school guy told me this........Get the car where you will work on it. Start the engine and slowly pour 5-6 ozs light weight (hyd or 20wt) oil into carb/TB etc, shut it off when your done pouring in the oil. Turn engine off and let sit at least 4 hrs. Now when you unscrew the plugs they will have oil coating on the inside of the plugs to help lube them. The loosen, add penetrating oil is still all good too. That's what Lester did for over 45 years, with hardly any problems.
 
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