Author Topic: Blue Smoke  (Read 1442 times)

--leXXy--

  • Newbie
  • Posts: 2
  • Location: Sydney Australia
Blue Smoke
« on: 18 November 2009, 05:34 PM »
Long time since i left my last comment, my Mercedes 450SE has done over 200000kms and now is blowing out blue smoke at idle. However when driving under regular conditions it doesn't blow blue smoke, it only blows at idle speeds and sometimes 1000-2000 rpm, it also blows an enormous amount at 6000-7000rpm....help anyone? i know its worn parts but can anyone give me further details?

flutes

  • Classic
  • **
  • Posts: 353
  • Location: Sydney
Re: Blue Smoke
« Reply #1 on: 18 November 2009, 05:49 PM »
Sorry I can't offer any advice but "at 6000 - 7000rpm"?

Are you doing that in neutral or are you racing that puppy?

My 450SEL redlines at just under 6,000 and I've never been game to take it over 5,500.  I think it would explode if I did that.
Matt
1977 450SEL

TJ 450

  • W116 Addict
  • ****
  • Posts: 4,135
  • Location: Rockingham, Western Australia
    • Tim's Insulators Downunder
Re: Blue Smoke
« Reply #2 on: 18 November 2009, 07:21 PM »
If it's definitely blue smoke, then you may have worn piston rings or excessively worn valve guides. If the smoke is constant, then I would expect that the bottom end needs attention.

BTW, 6-7k rpm is asking for trouble if you have a standard M117, as the redline is about 6k.  8)

The first thing I would do, is a compression or leakdown test.

Tim
1976 450SEL 6.9 1432
1969 300SEL 6.3 1394
2003 ML500

WGB

  • W116 Addict
  • ****
  • Posts: 3,280
  • And on the eighth day he made the 116
  • Location: Perth - Western Australia
Re: Blue Smoke
« Reply #3 on: 18 November 2009, 07:31 PM »
I think 5,800 is the redline on a 450 motor.

It needs a compression leak down test to see what the rings are like.

You might be lucky and if this test is OK it might be valve guide seals.

Bill

Big_Richard

  • Guest
Re: Blue Smoke
« Reply #4 on: 19 November 2009, 01:30 AM »
It only blows at idle speeds and sometimes 1000-2000 rpm, it also blows an enormous amount at 6000-7000rpm....

Gee, I wonder why.

This is an enthusiasts group, not an abusers group.