What do I Unplug?
Thread Starter
Newbie
Joined: Aug 2005
Posts: 22
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From: Missouri Ozarks
1994 E420
What do I Unplug?
Since I drive a V8 (94 E420), I was instructed to "unplug the wiring harness" and turn the engine for 20 seconds after an oil change prior to starting to "prime" the timing chain followers.
Can anyone tell me where this is located, what it looks like and how do I unplug it?
Many thanks
Bill
Can anyone tell me where this is located, what it looks like and how do I unplug it?
Many thanks
Bill
Super Member
Joined: Dec 2002
Posts: 882
Likes: 2
From: Sherman Oaks
2004 C240, 2015 GL350 Bluetec
I've never heard of having to do that in any car after an oil change.
Where did you get your information from?
I have the inline 6 and I have never had to do that nor ever seen my mechanic do that on any car after just an oil change.
Someone is bound to know if this is true or not.
Where did you get your information from?
I have the inline 6 and I have never had to do that nor ever seen my mechanic do that on any car after just an oil change.
Someone is bound to know if this is true or not.
Thread Starter
Newbie
Joined: Aug 2005
Posts: 22
Likes: 0
From: Missouri Ozarks
1994 E420
I got it off of one of these threads but can't find it again. What they said was the tensioners on the timing chain go dry during an oil change and the engine should not be started until this was "primed" for 15-20 seconds by turning the starter without starting the engine. They suggested unplugging the "wiring harness" in order to do this. I am trying to find out what and where this might be.
Bill
Bill
MBWorld Fanatic!
Joined: Feb 2002
Posts: 1,311
Likes: 11
From: Manchester, CT
On the V8...there are 2 wiring harnesses...lower one goes to the starter, alt and battery and is a bear to get at IMO (unless you have a lift). Upper harness goes to FIs and sensors and the way MB used cheap plastic on them; I'd be afraid to mess around with them if they haven't be changed out recently.
You can pour some oil in the filter housing too before buttoning it up...its only a sec or 2 and a few rattles until the oil slops around anyway. I've never had a problem and if you use synthetic (I do) it might not be as bad sounding right after start-up after a change of oil. Just my 2 cents.
You can pour some oil in the filter housing too before buttoning it up...its only a sec or 2 and a few rattles until the oil slops around anyway. I've never had a problem and if you use synthetic (I do) it might not be as bad sounding right after start-up after a change of oil. Just my 2 cents.
MBWorld Fanatic!
Joined: Dec 2003
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thats the first ive heard of that and i used to be an apprentice motor mechanic at a benz shop.
i would just turn it on and go.
if the cars engine has just been rebuilt, or its just had NEW chain tensioners installed or something like that, then maybe. in which case, just unplug the coil, crank a few seconds, reattach coil.
if they even have a coil. its been a while.
i would just turn it on and go.
if the cars engine has just been rebuilt, or its just had NEW chain tensioners installed or something like that, then maybe. in which case, just unplug the coil, crank a few seconds, reattach coil.
if they even have a coil. its been a while.
