m112 c320 spark plugs change

[mattuk]

Hi all

Weather looks fine in January so I am planning to change spark plugs in mu c320 2001 96k miles

I've seen lots of diy so I am ok with the job but I need Your help to choose correct plugs.

MB wants £120, I think it's too much. Anyway I checked ECP and they got bosch super plus for £5.40 each with discount it works out just under £50 so sound. However I am not sure if these plugs are suitable for m112 v6?
Has anybody used these plugs from eurocarparts? Going further in halfords bosch super plus x4 cost £32! There is big gap between two shops and I am wonder if ecp is giving right stuff.


Please for Your advise
Thanks

 

[television]

I bought mine off Ebay and no problems at all with the NGK £99 for all 16

 

[Miffy]

rather you than me, have you looked at how hard to reach those rear plugs are? do you have a tool ready to pull the caps off?

 

[television]

I did this with only one hand and the details in the DIY section

 

[Miffy]

Matt, I suggest you have a quick read of malcolms post before you start

http://forums.mercedesclub.org.uk/showthread.php?t=69643

 

[television]

I just use a 17mm open ended spanner to remove the leads, if you can use 3/8 drive ratchet, UJ and extensions as space is limited I find 1/2 inch drive to bulky.

Removing the under trays saves a lot of hassle as you are bound to drop something it's a lot easier to retrieve!

I always start with a couple of easy access ones to get into the swing of it and then move straight to the hard ones and get them over a done with.

Getting the right spark plug socket can also help a lot, ones with slightly deeper reach and thin walls helps a lot.

Only having one hand at the time of doing mine I dropped loads down below, it was handy for once having a steep driveway for they all rolled to the rear of the tray and I could pull most out from underneath. Colin removed the last two plugs when in for a service

 

[dog68]

Don't forget to get some deep heat gel.. unless its just me getting old, LOL.

 

[mattuk]

Thanks for quick reply guys!

No I haven't wrench yet but I am going to make it myself unless I find one cheap somewhere.

So 17mm wrench? I've seen someone diy using 18mm flat wrench but I'll do both sizes on my one.
I got set of ratchets in few sizes with extensions + short and long spark plug sockets 14mm thread(is 14mm correct plugs isn't?) so I should get in on the back plugs. However my mate will help me with his tools(lots and lots of tools)

So you prefer NGK instead of bosch? I got nothing to ecp but £50 vs £100 in halfords for same plugs sounds a bit unreal.

 

[mattuk]

Matt, I suggest you have a quick read of malcolms post before you start

http://forums.mercedesclub.org.uk/showthread.php?t=69643

I just read it thanks

 

[mattuk]

Unless Halfords have a special on then ECP seems to always be cheaper by a long way, as I say I am a big fan of ECP they have good pricing and lots of stock but when planning ahead do check places like eBay and Amazon as you can also normally beat ECP prices as well.

Don't forgot local motor factors if you have one you may be surprised what they can offer, I'm pretty sure sparkplugs.co.uk is a run by a small motor factor in the North West.

On the subject of spark plug socket getting a good one can make all the difference, as I said one with thin walls and deep section for grabbing on the socket really do help.

No no I got nothing to ecp, I used it mostly if I need to get something but I just was wonder if I buy bosch plugs I will get real bosch plugs(no china copy)if u compare prices in this scenario only


If I won't forget I'll make pictures and show you what tools I got and if something missing you can point me?

 

[mattuk]

Malcolm I saw your magic wires tool made by you which does sexy job :-D

I want one like yours( instead of bending and cutting flat steel)
Can u please say how did u do it?
On your diy you mentioned 5/16 and cut open. I got exacly same type 5/16(imperial) but in hand looks too small . however getting compare flat open wrench size 17mm to this spanner looks exacly as you said 16.5mm. Is it definitely 5/16? I got few spares size 3/4 and 5/8 which look very similar to open wrench 17mm. Sorry for being pain now but using your help I can get it done correctly.

Also how much did you cut out to make opening? How many mm did u go of center?
Thanks

 

[television]

Yes that was the size 5/16 whit this will one size up on the BSF heads as the size changed just after the war.I just ground out enough so that the spanner went over the plug and thats about 16mm

 

[mattuk]

Yes that was the size 5/16 whit this will one size up on the BSF heads as the size changed just after the war.I just ground out enough so that the spanner went over the plug and thats about 16mm

I got it. I'll make one tomorrow and post back
If you don't mind what is the size in between sides?16mm is the size of the spanner isn't? from one edge to the other edge in straight line(in opening)I ?I could go to the car but I don't want to get all covers off while dark outside just to see if it fits.

Thanks


Ps so you prefer ngk plugs right?

 

[television]

I got it. I'll make one tomorrow and post back
Thanks

Ps so you prefer ngk plugs right?

I had the same problem,, what plugs ???? I read till I could read no more and settled on the NGK.......confusing for me as when British made it was GNK or NKG

 

[mattuk]

hi

here are some pictures of tools i will use

do i need more extensions or something else?

here is picture of tool i made using Malcolm's technology
red arrows show size 17mm. enough?

i still got "confused.com" what plugs... i read somewhere to avoid platinum plugs as these may cause misfires. did u hear that? what is you experience and opinion on that?
both bosch and ngk match MB plug codes and these are platinums so i don't know how platinums can cause misfires if recommended by MB. strange?

 

[television]

That looks like my spanner spot on and good on you.

Yes you only need short extensions

I did not use the platinum plugs,,,I dont think so anyway, I had also read of problems

 

[grober]

Because they are such a pain to remove/fit I would go for the longlife NGK Iridium plugs type BKR5EIX-11 for your car. check here http://www.ngkpartfinder.co.uk/ A set of 12 will set you back about £80 but you should not have to change them again for about 60K miles. Because they use a very narrow Iridium tipped centre electrode they require less HT to fire and resist fouling much better. Reputed also to smooth out idle and any slight part throttle misfires also.

 

[mattuk]

That looks like my spanner spot on and good on you.

Yes you only need short extensions

I did not use the platinum plugs,,,I dont think so anyway, I had also read of problems

I got extension but about 3 and 4 inches long. I think too long

On your diy I saw one about 20-30mm. Are you talking about this one?I think it's got hole in the middle

 

[television]

As long as there is enough clearance between the engine and the inner wing you should be OK with what you have.

If I recall correctly I had to push the plug socket over the plug, and then fit the ratchet handle as it was too long to go in in one lump, if that is clear enough.

 

[mattuk]

Yes I am with you TV thanks


I'll go for ngk as lots of members said.
Ps mb says every 4 years or 60k miles, my car done 30k miles but plugs have not been changed since 8years so it's defo time for new set