Install spark plugs when coils are changed??
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From: Nashville, TN
SLK55 AMG - Renntech Supercharged
Install spark plugs when coils are changed??
I'm installing new coils this weekend when I install the tuned ECU and TCU. Since I'll already have the spark plugs within reach, is it recommended to go ahead and install fresh plugs? I'm temped to cheap out and leave them in.
The CL's about to hit 90K miles.
The CL's about to hit 90K miles.
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05 CL65
At 90K I would. I didn't change mine when I replaced my coil, but my car only has 44,000 miles on it. Already had one coil replaced before I got it though so I was just replacing one. I plan to do plugs this next winter even though I will still be under 50,000 miles.
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SLK55 AMG - Renntech Supercharged
How did I know you were going to say that. Do you guys go a step colder?
If not, I'll likely go OEM, which I believe is Bosch FR7KPP33U+.
If not, I'll likely go OEM, which I believe is Bosch FR7KPP33U+.
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From: Nashville, TN
SLK55 AMG - Renntech Supercharged
I removed the coil packs and plugs this evening. The biggest PITA was when the rubber insulators (or whatever the heck they're called) get stuck on the plugs when the coils are removed. I think I spent more time removing them from the rear most plugs on both sides than I did on the teardown.
After finally getting the insulators out of the way, all the plugs were removed. The plugs appear to be the stock NGK's. Some were cracked along the porcelain and the passenger rear plug has some type of buildup on the electrode.
Plugs and coils will be replaced tomorrow. I'll wait until winter to repair the suspected valve cover leaks.
Here's a photo of some engine oil pooling at the passenger front plug.
Here's some photos of the stripped engine.
After finally getting the insulators out of the way, all the plugs were removed. The plugs appear to be the stock NGK's. Some were cracked along the porcelain and the passenger rear plug has some type of buildup on the electrode.
Plugs and coils will be replaced tomorrow. I'll wait until winter to repair the suspected valve cover leaks.
Here's a photo of some engine oil pooling at the passenger front plug.
Here's some photos of the stripped engine.
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From: Nashville, TN
SLK55 AMG - Renntech Supercharged
Agreed for sure.
I haven't purchased the plugs yet, as the stockers weren't in stock at my local Autozone. I do think it's best to go a step colder, but was reluctant until hearing back from the elders.
Last edited by Grip Grip; May 24, 2014 at 09:12 PM.
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CL65
I don't know how much of a difference it will really make going with a different plug, but I have stock replacements for what its worth. You gotta realize you just ran 11.5x stock with plugs that almost look to be original.
I'm sure anything new will be a plus. I'd just put stockers back in so you could use it this weekend, unless some could give you better advice.
I'm sure anything new will be a plus. I'd just put stockers back in so you could use it this weekend, unless some could give you better advice.
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From: Nashville, TN
SLK55 AMG - Renntech Supercharged
I don't know how much of a difference it will really make going with a different plug, but I have stock replacements for what its worth. You gotta realize you just ran 11.5x stock with plugs that almost look to be original. I'm sure anything new will be a plus. I'd just put stockers back in so you could use it this weekend, unless some could give you better advice.
I'm sure anything new will be a plus. I'd just put stockers back in so you could use it this weekend, unless some could give you better advice.
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CL65, FJ80, Sportsmobile 4x4, Model X Plaid
Look for oil coating the Red insulators..
The front passenger side of the engine near the oil filler / cap area is where the oil will drip right into the coil holes if you accidentally miss and spill the oil when filling it.. all it takes is a tiny bit and it'll flow down right into the spark plug holes.. almost a perfect path for the oil to go.
The oil will make its way coating the red insulators and eventually cause it to arc..
That's why I don't trust anyone doing even the oil change..
Another thing that I did was take a hemostat and wrapped paper towel strips and used simple green to clean out the spark plug cavities.. all 24 cavities..
I even took a videoscope and looked thru the spark plug hole to check the tops of the piston and cavity walls..
The front passenger side of the engine near the oil filler / cap area is where the oil will drip right into the coil holes if you accidentally miss and spill the oil when filling it.. all it takes is a tiny bit and it'll flow down right into the spark plug holes.. almost a perfect path for the oil to go.
The oil will make its way coating the red insulators and eventually cause it to arc..
That's why I don't trust anyone doing even the oil change..
Another thing that I did was take a hemostat and wrapped paper towel strips and used simple green to clean out the spark plug cavities.. all 24 cavities..
I even took a videoscope and looked thru the spark plug hole to check the tops of the piston and cavity walls..
Last edited by NRL; May 24, 2014 at 04:18 PM.
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From: medina ,ohio
05,cl65;33ford3wc.
Did my 65 two years ago with much lower mileage than yours, all the plugs looked excellent except the right rear which were moderately fouled, perhaps that's common. I use Techron once a year; mostly open road miles.
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From: Nashville, TN
SLK55 AMG - Renntech Supercharged
Sorry, but I didn't mean to come across as if I actually know for a fact it's from carbon buildup. I did a google search and that's the first thing I found.
I cleaned the best I could and attached 2 foot piece of 5/8" hose to the end of my shop vac and lowered it down in the the plug hole in the head. This should have gotten out all the loose dirt.
Surprisingly, the passenger coil was new. It must have been replaced by the dealer before I bought the car.
I'm leaning toward that conclusion myself, as the car was running perfect prior the the plug swap.
Look for oil coating the Red insulators..
The front passenger side of the engine near the oil filler / cap area is where the oil will drip right into the coil holes if you accidentally miss and spill the oil when filling it.. all it takes is a tiny bit and it'll flow down right into the spark plug holes.. almost a perfect path for the oil to go.
The oil will make its way coating the red insulators and eventually cause it to arc..
That's why I don't trust anyone doing even the oil change..
Another thing that I did was take a hemostat and wrapped paper towel strips and used simple green to clean out the spark plug cavities.. all 24 cavities..
I even took a videoscope and looked thru the spark plug hole to check the tops of the piston and cavity walls..
The front passenger side of the engine near the oil filler / cap area is where the oil will drip right into the coil holes if you accidentally miss and spill the oil when filling it.. all it takes is a tiny bit and it'll flow down right into the spark plug holes.. almost a perfect path for the oil to go.
The oil will make its way coating the red insulators and eventually cause it to arc..
That's why I don't trust anyone doing even the oil change..
Another thing that I did was take a hemostat and wrapped paper towel strips and used simple green to clean out the spark plug cavities.. all 24 cavities..
I even took a videoscope and looked thru the spark plug hole to check the tops of the piston and cavity walls..
Surprisingly, the passenger coil was new. It must have been replaced by the dealer before I bought the car.
I'm leaning toward that conclusion myself, as the car was running perfect prior the the plug swap.
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From: Sacramento
W221 2013 S550 Rwd, W221 2010 S550 Rwd
I would not use autolites. Not saying they are horrible plugs but they are just not fit to put your 65. There was a thread in the 220 forum where a gentlemen opted to use autolites instead of ngk on his s600 v12 One of the plugs tip literally broke and fell into the cylinder ... damaging it. He ended buying a used motor and swapping them. Grip the decision is yours but as an automotive enthusiast and certified tech I would advise you to use the ngk plugs always. Goodluck my friend
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From: Nashville, TN
SLK55 AMG - Renntech Supercharged
I would not use autolites. Not saying they are horrible plugs but they are just not fit to put your 65. There was a thread in the 220 forum where a gentlemen opted to use autolites instead of ngk on his s600 v12 One of the plugs tip literally broke and fell into the cylinder ... damaging it. He ended buying a used motor and swapping them. Grip the decision is yours but as an automotive enthusiast and certified tech I would advise you to use the ngk plugs always. Goodluck my friend
Thanks for the info, but the plugs are fully installed along with the coils. The car is complete awaiting the TCU.
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From: Sacramento
W221 2013 S550 Rwd, W221 2010 S550 Rwd
https://mbworld.org/forums/s-class-w220/532232-04-w220-s600-cylinder-7-only-misfire.html
Check out his thread , he did an awesome job swapping motors. I would hate to see you have the same problem over a spark plug. Put ngks in grip !!
Check out his thread , he did an awesome job swapping motors. I would hate to see you have the same problem over a spark plug. Put ngks in grip !!
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From: Las Vegas
2016 S65 AMG coupe, 2010 E63, 2015 Z06/z07 m7 vert 735rwhp, 2000 f-350 crewcab w/ 16" kelderman kit
Get the Autolites out ASAP!! I have done plugs in my 65 and used colder range ngk plugs. I think i spent $70 on all the plugs. They are NGK v-power BKR7E 4644
I run a repair shop for a living and can't tell you how many problems come from autolite plugs!
I run a repair shop for a living and can't tell you how many problems come from autolite plugs!
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From: Nashville, TN
SLK55 AMG - Renntech Supercharged
Thanks and Thanks.
Thanks for the advice. I just placed an order for the NGK's you referenced off Amazon. They won't be installed right away, but within a few weeks. I'll swap sooner if I detect missfiring or a rough idle.
Last edited by Grip Grip; May 25, 2014 at 07:59 PM.
