Spark Plug Change

Page may contain affiliate links. Please see terms for details.

BaldGuy

MB Enthusiast
Joined
Jun 1, 2002
Messages
4,414
Location
Berkshire, London & Devon
Car
No longer a Benz...
My Benz needs an "A" service in 1K's time and also its done 57K with no plug change, Should I have them changed as Greenoaks my local stealer want £226 for just a plug change and another £226 for the service....

Oh for those who don't know its a 2.4 V6 lump...

Value your comments
 
This was almost exactly the same as predicament as my car last April, it was due an 'A' service at approx 56k miles. I decided that I would wait until the next service as 12 sparks came to approx £60 and labour at approx 2 hrs just for changing them, with a little negotiation I think I got the stealer down to roughly £180 parts and labour for the job.

At this point in time I don't regret not changing them back then as the car is going great guns. I seem to recall reading somewhere (or it may have been advice from G.F.) that the sparks should be changed on the 2.4 V6's approx every 60k to 70k miles.

I'd be interested in your decision Greg, btw how are the cosmetic repairs coming on?

S.
 
Are they still the original plugs? If so I would change them before they start dropping bits of ceramic and crud into your cylinders. I may be totaly wrong on that one, but it's what I'd do.

This might be of interest to you Link about plugs
 
p.s. that's £180 ex VAT so with the taxman's slice it's not far off from your quoted £226.

S.
 
Steve,

Dont ask about the repairs....infact I feel really dis-interested with my Benz at the moment, it looks like I've done all of the stages of the Network Q at the moment which is totally not like me.....
Not good times.....
 
Greg,

You know who to ask if you want some plugs at a special price. <img src="http://www.mbclub.co.uk/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt=';)'> &nbsp;Either NGK, Champion or Bosch. I think Champion are OE on most mercs but NGK are regarded by many as the best, wont be anywhere near £60 with vat and delivery.

They can be a bit awkward on the V6's but we recently stripped the ignition leads, coils and plugs out of a brand new C240 W203 for R&amp;D. The hardest part was removing the plug leads as they were very tight and having the two plugs per cylinder makes them a bit tight for room.

If it was me I would do it myself or get a friendly mechanic to do it in the evening or weekend, we have one who we put a lot of work his way and he charges us £15/hr. <img src="http://www.mbclub.co.uk/iB_html/non-cgi/emoticons/biggrin.gif" border="0" valign="absmiddle" alt=':D'>
 
Greg,

Hang in there mate... I felt exactly the same way when mine got smacked, total disinterest in the car while it was damaged. My enthusiasm soon returned once I got the car back in perfect condition. Hopefully you'll get it back asap.

S.
 
Bosch are OE on most mercs...

Dont know about the 2.4 V6 as it has twin spark &nbsp; <img src="http://www.mbclub.co.uk/iB_html/non-cgi/emoticons/confused.gif" border="0" valign="absmiddle" alt='???'>
 
how often shoul plugs be changed on the 4cyl engines?
 
bump?

4 Cylinders rock - who has the answer?

Greg - cheer up - what's wrong anyhow - if you have the car back?

My mate has only had his E36 M3 a short while and he got T-boned by a fiesta :(
 
Last edited:
hi, koolvin-re spark plug change.

on my c200,1997/p,4 cylinder-every 18,000miles-(only if yours are the single electrode type.)

check your maintenance booklet-should have the details for your car
 
Vinay will be running one heat range cooler on the plugs, and changing them every 6000 miles I reckon :)

Mark
 
Originally posted by Koolvin
what's a heat range cooler?

LOL - Spark plugs are catagorised into "heat ranges"

The heat range of a spark plug is its ability to dissipate heat from the combustion chamber to the cylinder head. The heat range, of a spark plug depends primarily on the length of the insulator nose. The heat from the combustion is transferred from the insulator nose through the center electrode to the plug housing, and from there it goes to the cylinder head

During the combustion process the tips of the spark plugs are heated until they glow. This heat must travel from the tip through the shell and ultimately into the water jacket of the cooling system before the next compression stroke. If the tip is still glowing when the piston comes up with fuel - you get pre igintion or pinking

therefore a "cold" plug has a shorter insulator nose, which minimizes the amount of surface area exposed to the combustion gases and therefore the heat absorbed

Most turbo applications use this type of plug because of the tremendous heat generated by the turbo. A colder plug can also minimize the risk of pre-ignition and detonation, however if the plug is to cold there is risk of fouling during extended periods of idling and low-speed "round town" type operation.

Spark plugs are not just spark generators - and their selection can be crucial in getting a car to run nicely.

So your car will be running "A heat range cooler" :D

Mark

Phew !
 
Originally posted by Mark300SL
LOL - Spark plugs are catagorised into "heat ranges"

The heat range of a spark plug is its ability to dissipate heat from the combustion chamber to the cylinder head. The heat range, of a spark plug depends primarily on the length of the insulator nose. The heat from the combustion is transferred from the insulator nose through the center electrode to the plug housing, and from there it goes to the cylinder head

During the combustion process the tips of the spark plugs are heated until they glow. This heat must travel from the tip through the shell and ultimately into the water jacket of the cooling system before the next compression stroke. If the tip is still glowing when the piston comes up with fuel - you get pre igintion or pinking

therefore a "cold" plug has a shorter insulator nose, which minimizes the amount of surface area exposed to the combustion gases and therefore the heat absorbed

Most turbo applications use this type of plug because of the tremendous heat generated by the turbo. A colder plug can also minimize the risk of pre-ignition and detonation, however if the plug is to cold there is risk of fouling during extended periods of idling and low-speed "round town" type operation.

Spark plugs are not just spark generators - and their selection can be crucial in getting a car to run nicely.

So your car will be running "A heat range cooler" :D

Mark

Phew !

Woah!!! Interesting and written so nicely, Guess what I'll be talking about in the pub this evening? (nothing cause i'm at home configuring this software) :(
 

Users who are viewing this thread

Back
Top Bottom