scared of spark plugs

mike102

Senior Member
Joined
Mar 20, 2009
Messages
123
Reaction score
0
Location
polperro cornwall
Your Mercedes
1990 300 E class
Dear Members.
I'm new to owning a Mercedes iv'e had one for a month now, It's a 300E i love the car and want to maintain it as much as possible by myself.
I am not familiar with the engine and was surprised when i took hold of a HT lead for a spark plug. It just rotated in it's housing and had thought i had snapped a thread, Please could someone tell me how the sparks are fitted for replacement and can i do them myself. In the past my cars always had sparks that i had to remove with a socket/thread. Just hope i haven't broke something. Please give me some assurance.
Thanks.
Mike.
 

Sam.slc

Senior Member
Joined
Apr 7, 2009
Messages
48
Reaction score
0
Hey, Welcome Mike

I presume your car is a W124? Without seeing the actual lead it is difficult to say, but these things are hardy and will put with a bit of twiddling here and there.
Have you tried getting the Haynes Manual for the car or the Technibooks both are quite easy to follow and will ease you into car care. You can find them online as well. Someone will be along in a mo with diagrams and all sorts to help you out. The folks are great on here
 
OP
mike102

mike102

Senior Member
Joined
Mar 20, 2009
Messages
123
Reaction score
0
Location
polperro cornwall
Your Mercedes
1990 300 E class
  • Thread Starter
  • Thread starter
  • #3
spark plugs

Thanks for the come back Sam/slc.
Yeh i'm a bit knew to these forum things and hope i can feel free to ask for help without seeming like a dip-stick, I will check out the Haynes, but for now Thanks.
Mike.
Oh and thankyou for the welcome.
 
Last edited:

kbekl

Senior Member
Joined
Mar 22, 2009
Messages
86
Reaction score
0
Age
40
Location
manchester
Your Mercedes
1998 E300td
not quite sure what you have done

have you removed the ht lead off the sparkplug to show the white ceramic or is it still black from what you said it the first post i would think the ceramic has snaped giving you the ability to turn it or you could have pulled the lead out and left the cover on the spark plug which is what you are turning

have you tried to get a socket on the plug and see if it will undo ?
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
Hello mike102 and a big welcome to you:D.

The plug leads normally just screw into the plug cap, and the plug cap just pulls off in the normal way, under the cap you have a normal sparking plug.

The plug caps can get tight and could be best to lever them off if possible
 

Sam.slc

Senior Member
Joined
Apr 7, 2009
Messages
48
Reaction score
0
Hey Mike

Feel free to ask anything, thats what the place is for. Is your car a W124?
 
OP
mike102

mike102

Senior Member
Joined
Mar 20, 2009
Messages
123
Reaction score
0
Location
polperro cornwall
Your Mercedes
1990 300 E class
  • Thread Starter
  • Thread starter
  • #7
KBKEL.
What happened was, I was just checking the lead directly on the plug and as i turned the sleeve covering the plug i noticed that the plug itself turned along with it. See what worries me is, Do the plugs just swivel and pull-out, or are they a screw fit, and if not, have i broken something.
Thanks
Mike.
 

kbekl

Senior Member
Joined
Mar 22, 2009
Messages
86
Reaction score
0
Age
40
Location
manchester
Your Mercedes
1998 E300td
they are normal screw types

is the car running fine ?

it sounds like you have a loose plug i would get the lead off and see if it loose or damaged

i wouldnt have thought moving the ht lead would damage a plug to that extent
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
All plug caps just pull or lever off, the angle connector just screws on, you have not broken anything
 
OP
mike102

mike102

Senior Member
Joined
Mar 20, 2009
Messages
123
Reaction score
0
Location
polperro cornwall
Your Mercedes
1990 300 E class
  • Thread Starter
  • Thread starter
  • #10
Hi Television, Thanks for the welcome.
I am wondering if all my spark plugs are loose, when i get hold of the sleeve covering the plugs, i am able to turn the plugs and can visibly see it rotate either left or right, their is a marker on the plugs which i can see, it seems like i could literally just pull the plugs out with no effort.
Thanks
Mike
 

kbekl

Senior Member
Joined
Mar 22, 2009
Messages
86
Reaction score
0
Age
40
Location
manchester
Your Mercedes
1998 E300td
have you only checked one or are all the same ?

what year is the car ?
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
Its not a good situation if the plugs are loose, you must pull off the caps to expose the white porcelain with the screwed thread on top and do them up tight, the plugs in your car are just plain simple plugs
 

kbekl

Senior Member
Joined
Mar 22, 2009
Messages
86
Reaction score
0
Age
40
Location
manchester
Your Mercedes
1998 E300td
if they were loose would have thought their would be some sort of running problem due to the compression when running.
also would the pressure not evetually force the plugs out ?
 

exeng

Senior Member
Joined
Sep 6, 2007
Messages
101
Reaction score
0
I would just assume the plug is loose but if the threads are stripped which i doubt it is you can repair this without any issue and there is no need to remove the head
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
if they were loose would have thought their would be some sort of running problem due to the compression when running.
also would the pressure not evetually force the plugs out ?

I have seen cars where the plug has gone through the bonnet.

I wonder if the porcelain is just broken, easy to see once the cap is pulled off
 
OP
mike102

mike102

Senior Member
Joined
Mar 20, 2009
Messages
123
Reaction score
0
Location
polperro cornwall
Your Mercedes
1990 300 E class
  • Thread Starter
  • Thread starter
  • #17
Dear All.
Thanks for all your replies, but what i actually mean is, when i turn the sleeve on the plugs, The plugs themselves turn as well. Does this mean that they are loose and need tightening up, or is there some play with them.
Excuse me if i come across as stupid.
Mike
 

kbekl

Senior Member
Joined
Mar 22, 2009
Messages
86
Reaction score
0
Age
40
Location
manchester
Your Mercedes
1998 E300td
is the sleeve the ht lead end ?

if it is i would say they need tightening up asap

i have never know a plug to be loose

and i dont think they make plugs that are just pushed in due to the pressure they are under

so from my knowledge i would say they need to be tight
 
OP
mike102

mike102

Senior Member
Joined
Mar 20, 2009
Messages
123
Reaction score
0
Location
polperro cornwall
Your Mercedes
1990 300 E class
  • Thread Starter
  • Thread starter
  • #19
the sleeve is the one that holds the plug itself, and if i turn the sleeve the plug can be seen to move with it.
 
OP
mike102

mike102

Senior Member
Joined
Mar 20, 2009
Messages
123
Reaction score
0
Location
polperro cornwall
Your Mercedes
1990 300 E class
  • Thread Starter
  • Thread starter
  • #20
dec.
Looking at the image you sent, it looks like it's the ceramic part of the plug that is turning. Is this okay, or do they need replacing.
Thanks.
Mike.
 
Top Bottom