Jon2007E63P30

So here goes my shot at a DIY for replacing M156 engine spark plugs.

As you saw in my thread posted last night https://mbworld.org/forums/w211-amg/...-insanity.html

I had dis-assembled the intakes and air boxes to add a reflective tape used in Indy and F1 cars for reflecting heat away from the intake air. Besides trying to reduce intake air temp, it looked cool.
So here we are in the AM with all the parts on the side.



The top of the engine is easy to access. First I loosened up the wires to the coils on the top of each spark plug. You should be able to pinch the connector to un-clip it, but I found just using a screw driver to be easiest.



The torx screws holding on the coils were lightly hand tight and easy to remove. However, the one closest to the fire wall on the left side had limited clearance. Took a mix of sockets and adapters to loosen and replace this one. That is the fuel line.



I did not bother to buy the appropriate spark plug socket since I had a deep 14mm socket. However, to remove the spark plug once completely loose, I just stuck the spark plug boot/coil in there and captured it. This happens to be a picture of a ne wplug ready to go in.

Jon2007E63P30

Next, I would clean out the spark plug seat with a WD-40 soaked paper towel attached to a heavy wire. I would push it in and rotate it to clean the seat. You can see the debrise here.



I blew out anything else with an air hose. All nice and shiny. The flash on the camera had a neat effect.



Next, I got a new plug and transferred the dielectric grease from one to the other. Here is an old and new plug.



Because I did not have the right spark plug socket, just as I used the boot to remove the old one, I used the boot for the new one. Just insert and make a couple turns to engage the threads. After that I went in with my 14mm socket. It was easy to feel the washer crush and the plug firmly seat. Remember, this is aluminum!!!



After that, just put the torx screws back hand tight (lightly, you will be able to tell how tight from how easy they came off). Now repeat 7 more times.

Jon2007E63P30

Next, I re-assembled the intake. This is a picture of the Y tube where it mounts to the intake manifold. I cleaned it up, treated with 303, and slide it right on. It just clips on with those 2 big tabs.



Next put on the foam rubber spacers/insulators



Then the lower halves of the air boxes and the new filters. These just clip into place at 3 points. One big spring in the center. See the 3 points here.




So now we are at this point

Jon2007E63P30

Next, you need to put on the top of the air boxes that have the MAF sensors. I wiped on some silicon spray so they were easier to insert into the Y pipe. Make sure the air filters are all correctly in place and then screw in the 5 torx screws. Then tighten the large hose clamps between the Y pipe and the upper air boxes (which I just realized, I forgot to do!!!!). Then re-attach the air tube leading from the front grill to the air box intakes and you are here.



After this I changed the oil. Rolled out into the sun it looked like this.



Lastly, a note about the old plugs. The front right plug for some odd reason had new oil on the hex nut. None of the others were like this and I have to assume it happened in production. When you have a real leak from the valve cover there is usually more oil and it is used. All the plugs were between 0.039 and 0.041 gap, essentially zero wear. Makes me think I should have just cleaned them and re-used. They are on my shelf for "in case".



That's it, I hope some of you find it useful.

I should note that new plug, new air filters, new oil makes a real performance difference on a 60kmile engine.

MB_Forever

Great write-up Jon....

I will definitely use this post as reference when it's time to change my spark plugs

blk07bruins63

Nice info and thanks for sharing!!!!

lilg210

Are there 16 spark plugs for an 05 E55??? I could have sworn someone told me there were???

shardul

iTrader: (1)

yes the e55 has 16 plugs

lilg210

Thanks I was getting worried I bought 16 Pulse plugs and they aren't cheap, especially when you buy 16

400RWHP

Beautiful write up and even hotter car

The only thing I would be cautious about is the paper towel/WD-40 cleaning idea. You may want to use a little WD-40 while the old spark plug is still installed, just a little bit to loosen the debris, then blow it out with an air compressor at a healthy PSI. Doing it without a spark plug installed makes me very nervous as there is a portion of debris that could be forced down into the cylinder while you are attempting to clean it. Maybe this is what you did and I misunderstood. Just hate any chance of anything getting inside a $30,000+ engine

Regards

izzyz28

I take an air hose and blow any loose debris out before disassembly. Anything else that may fall in there is too small to cause any harm.

Jon2007E63P30

In fact I did that over the engine before taking off the boots over the plugs. The stuff I was picking up was mainly the small amount of carbon that made it past the threads. In my picture you see a small piece of aluminum from the threads.

Inside the area protected by the boot, it is clean as can be.

Yuille36

Great write up, my indy told me that sometimes these plugs don't want to come out, after many years, so don't wait until the 100K mark. What was the torque setting for tightening these plugs down. And did you use anti-seize compound on the plugs. This is straight forward, so when it comes time, I will remember your write up thank you.

thumper823

didnt want to clean and reuse the K&N's you pulled out?

outrun

subscribed

Jon2007E63P30

I still have them. I need to go out and buy the re-oiling kit.

Yes, I was lazy.

Yuille36, the change interval for the plugs is 60k or 5 years. Not 100k. The torque setting is 15-18.5ft-lb. You should be able to find it in your owners manual, page 488 (2007 E)

jpohl402

Beautiful write-up
I just had mine changed as well (05 - 75k)
however they were just like yours - essentially ZERO wear.
Oh well....

Yuille36

Thank you, Sir

fly2nite

Planning to undertake this week, many thanks for the writeup! One question, you mentioned a performance increase after new plugs, filters and oil change...Hypothetically, if the existing plugs are still good, is there a performance increase to be had simply by installing new ones? I never thought of it as anything more than a spark as long as the gap is right, but I realize I'm showing my ignorance in admitting that. Did you apply any anti-seize on the new plugs?

jonthaynes

good

Jon2007E63P30

Probably the air filters has most effect. Maybe the supposedly cooler air through the intake with the reflect-a-gold. I agree, the old plugs looked pretty good.

No, I did not use anti-seize. Given my if it was a garage queen, then I might have done that.

infantry

Subscribed! I posted in the other thread as it was more on topic about your thermal temps.

otakki

Awesome! Subscribed.

Jon2007E63P30

Damn, never mentioned the plug part numbers.

Directly from the owners manual under "Technical Data" "Electrical System"
NGK ILZKAR7A10
Quick google shopping shows a place for $9.35, but sure there are many others.

HamYoYo

This DIY just saved me $580.00!!! Thank you VERY much, great write up!!!!