Mercedes-Benz Forum banner

1 - 6 of 6 Posts

Registered
2004 S55 , 2005 S55 , 2004 S430
Joined
77 Posts
Discussion Starter #1
So one of my coils on my s55 appears to be leaking oil or some kind of fluid. I've cleaned it off several times and it returns. It can't be coming from valve cover cause those have been resealed and painted. Actually had to repair right valve cover cause magnesium had oxidized away creating small hole. There is no oil in air cleaner assembly and the oil is only on the one coil and only on top where the resin is used in the manufacturing. I know the old canister style coils in the 60's thru the 70's had oil inside them but these modern coils I thought were constructed differently. It seems to be working no misfires and I have a new one bosch coil to replace it with. Was just curious has anyone else seen this on there coils? When i get this one off I'm going to cut it open to see what its insides look like. Maybe they can bleed.
2611794
2611795
 

W220 Moderator
S500 W220 SLK320 R170 C200 CDI W203 Peugeot Expert Van
Joined
5,851 Posts
Like you, I didn't think these Coils were Oil filled, I'm very keen to see what you find when you dissect it ;)
 

W220 Moderator
S500 W220 SLK320 R170 C200 CDI W203 Peugeot Expert Van
Joined
5,851 Posts
I know the old ones did, but AFAIK the newer style are solid state ;)
 

Registered
2004 S55 , 2005 S55 , 2004 S430
Joined
77 Posts
Discussion Starter #5
Well I switched it out with a new one and cut it open. Didn't find any oil but in one part of it the epoxy looked like it was kinda dehydrated looking or maybe heated and breaking down. I suppose it's a mystery, I dont like mysteries. I guess it could seep up thru the bolt if the valve cover threaded hole was breached then creep over the edge of the hole in coil and collect on top of coil. That's the only explanation I can come up with. I'm going to keep my eye on it and if it continues on that coil location then I just trashed a good coil for experimental purposes. Oh well learning is so fun.
20191122_100555.jpg
 

W220 Moderator
S500 W220 SLK320 R170 C200 CDI W203 Peugeot Expert Van
Joined
5,851 Posts
Hi,

Thanks for that, I have to say that was what I expected you to find .............. Solid State !!

A few years back we were seeing a lot of Vauxhall Cars which had an expensive "Cassette style" 4 cylinder all in one Coil Pack that would fail regularly, so I took one to bits and found exactly the same construction, the idea was to rebuild them using good coils, but in the end, although it worked it turned out to be non cost effective ;)
 
1 - 6 of 6 Posts
Top