2016 Mercedes E350 spark plugs 60k mi

[The Artillerist]

Maintenance schedule specifies 60k mile interval because it’s a multi-spark per tact affair. And yet, the plugs look nearly new, as far as I’m concerned

New on the left:

5 old ones on the left and 2 new ones on the right

 

[AZjeff]

You follow the maintenance schedule or you don't...

 

[The Artillerist]

You follow the maintenance schedule or you don't...

I do. Don’t all car enthusiasts? ()

 

[dogememe]

I do. Don’t all car enthusiasts? ()

Not even close haha.

 

[The Artillerist]

Not even close haha.

Pan was intended on my part . I’ve browsed this site for a while before joining. Had to pick up my jaw more than several times. Some of us have abusive relationship with our mechanical pets

 

[loneryder]

Mine is approaching 60k and I’ve seen a number of reports saying the same thing as you. Thanks for posting. Going to leave them in for a while.

 

[BHopkins]

I recall seeing similar results when I changed plugs at the 60k interval, on my '14 E350.

My opinion of preventative maintenance, is that you aren't waiting until a part is starting to fail. Instead, you want to replace it before it wears so much that it starts to affect performance. So I'm ok with replacing plugs that look like there is no visible wear.

 

[The Critic]

Mine is approaching 60k and I’ve seen a number of reports saying the same thing as you. Thanks for posting. Going to leave them in for a while.

Some of the 276 motors are now at a 50K interval.

 

[Bailes1992]

Those plugs actually look quite worn to me. The gap is quite large and the shape of the grounding electrode is somewhat different.

 

[ka9mnx]

I don't change plugs by schedule. I pull, inspect, reinstall.

 

[Escape08]

Looks new but need to correct gap adjustment

 

[AZjeff]

Let's get every last mile out of these plugs..

Denso says the plug on the right is worn. Kinda looks like the difference in OP's new and used plug.

 

[JavierH19]

You could've said they had 10k and i'd've believed it. Looks great for 60k.

 

[ARCOgraphite]

I've pulled Ir at 100k and they looked servicable. No performance or mileage benefit from the new plugs was seen.

It is probably more of a health checkup than a need for plugs.

and then MB USA throwing a bone to MB service depts.

Ny wife's older subaru scheduled plugs at 60k mi for pricey Ruthenium fingernail plugs
That 60K was the same interval as the old platinum electrode plugs.
I left them alone.
Car was running better than new at 90K when traded in. As could be expected.

 

[JohnnyG]

Yeah, the gap is a little large. Maybe that's why they want you to change them at 60k?
While we're on the subject of Mercedes spark plugs, have you ever heard of "indexing" being required by MB? I read somewhere that genuine MB plugs are made to index so that the open side of the gap faces the incoming fuel/air charge. I just wondered it there was any truth to that or not.

I also heard that race engine builders do that, but have no evidence that it's true.

 

[ARCOgraphite]

Yeah, the gap is a little large. Maybe that's why they want you to change them at 60k?
While we're on the subject of Mercedes spark plugs, have you ever heard of "indexing" being required by MB? I read somewhere that genuine MB plugs are made to index so that the open side of the gap faces the incoming fuel/air charge. I just wondered it there was any truth to that or not.

I also heard that race engine builders do that, but have no evidence that it's true.

I can think of no common manufacturing method for MB to do that from the factory. There is no easy way to do that on a passenger car with the heads on. Pentroof heads with center plug location and large gap it just doesn't matter.

Certain closed chamber indexing is done on 2V heads for better burn and more torque. This is done with heads off or plugs with a witness mark so you know which way the electrode is facing, many race plugs are side gapped, I have seen some that have side gap electrode 'pins" in the shell. So here there will be no inrush vortices around a "shadowing" welded electrode strap.

I don't know what NASCAR or F1 is doing currently. or Piston engine Aircraft for that matter.

- Ken

 

[loneryder]

Yeah, the gap is a little large. Maybe that's why they want you to change them at 60k?
While we're on the subject of Mercedes spark plugs, have you ever heard of "indexing" being required by MB? I read somewhere that genuine MB plugs are made to index so that the open side of the gap faces the incoming fuel/air charge. I just wondered it there was any truth to that or not.

I also heard that race engine builders do that, but have no evidence that it's true.

That's true.(indexing)

I can think of no common manufacturing method for MB to do that from the factory. There is no easy way to do that on a passenger car with the heads on. Pentroof heads with center plug location and large gap it just doesn't matter.

Certain closed chamber indexing is done on 2V heads for better burn and more torque. This is done with heads off or plugs with a witness mark so you know which way the electrode is facing, many race plugs are side gapped, I have seen some that have side gap electrode 'pins" in the shell. So here there will be no inrush vortices around a "shadowing" welded electrode strap.

I don't know what NASCAR or F1 is doing currently. or Piston engine Aircraft for that matter.

- Ken

Sometimes they need small adjustments by the installer. The plugs come with proper gap.

I can think of no common manufacturing method for MB to do that from the factory. There is no easy way to do that on a passenger car with the heads on. Pentroof heads with center plug location and large gap it just doesn't matter.

Certain closed chamber indexing is done on 2V heads for better burn and more torque. This is done with heads off or plugs with a witness mark so you know which way the electrode is facing, many race plugs are side gapped, I have seen some that have side gap electrode 'pins" in the shell. So here there will be no inrush vortices around a "shadowing" welded electrode strap.

I don't know what NASCAR or F1 is doing currently. or Piston engine Aircraft for that matter.

- Ken

If you ever had plugs not indexed properly you would know it. Runs terrible. I put some Bosch plugs in a Chrysler V6 and it ran terrible. Took it to a mechanic and he put in original plugs. Said the open side of the plug was facing the cylinder wall.

 

[The Critic]

Yeah, the gap is a little large. Maybe that's why they want you to change them at 60k?
While we're on the subject of Mercedes spark plugs, have you ever heard of "indexing" being required by MB? I read somewhere that genuine MB plugs are made to index so that the open side of the gap faces the incoming fuel/air charge. I just wondered it there was any truth to that or not.

I also heard that race engine builders do that, but have no evidence that it's true.

It is true.

https://automotivetechinfo.com/wp-content/uploads/2021/04/Spark-Plug-Indexing-for-Direct-Injection-Engines-QEC-ES.pdf

 

[dogememe]

It is true.

https://automotivetechinfo.com/wp-content/uploads/2021/04/Spark-Plug-Indexing-for-Direct-Injection-Engines-QEC-ES.pdf

Interesting. I've never heard of that. You learn something new every day!

 

[JohnnyG]

It is true.

https://automotivetechinfo.com/wp-content/uploads/2021/04/Spark-Plug-Indexing-for-Direct-Injection-Engines-QEC-ES.pdf

Whoa! Thank you very much! Melted piston! Cripey!