MBE 4000 oil leak while idling

jjoerger · Dec 13, 2009

I have a 2006 Freighliner Columbia with a Mercedes MBE 4000.
I am having to idle this weekend and have noticed that I am leaking oil from just behind the turbo. Has anyone else had this problem? I think it is being caused by the idling as the truck does not use any oil between services. Any information would be appreciated.

layoutshooter · Dec 13, 2009

I have not noticed that problem with mine.

guido4475 · Dec 13, 2009

jjoerger said:
I have a 2006 Freighliner Columbia with a Mercedes MBE 4000.
I am having to idle this weekend and have noticed that I am leaking oil from just behind the turbo. Has anyone else had this problem? I think it is being caused by the idling as the truck does not use any oil between services. Any information would be appreciated.

Alot, not all, trucks will do that while idling.I forget the correct term for it, cylinder wash, or something like that.By raising the idle it will help a little, but still do it, and it will smoke excessively when you take off upon aceleration until the turbo burns all of that oil out of it.The only cure for it, as far as I know, is not to idle.Even my van will do that when I idle it.

jjoerger · Dec 13, 2009

Thanks for the reply. I found this on a web site that I think explains the problem.

"Diesel engines were designed to operate at peak efficiency running wide open. As there are no spark plugs, cylinder temp., obtained by compressing air in the compression cycle, is necessary to ignite the fuel. At low idle the cylinder temp. drops leading to incomplete combustion. This incomplete combustion leads to carbon build up on the valves, in the oil (crankcase), on the fire deck of the head and the dome of the piston along with fire rings on the piston. Engine “slobbering”, what appears to be oil, out of the air box drains and the exhaust are other side effects. As worn oil control rings will also give you both of the last two items this is often cited as the cause of an engine “slobbering”. The irony is that the carbon build up in the oil will lead to worn oil control rings."

So I guess I'm just slobbering this weekend.

guido4475 · Dec 13, 2009

You ought to be ashamed of youself, slobbering like that.Now go sit in the corner until youre Father gets home.

Dynamite 1 · Dec 15, 2009

first, definatley idle the engine up. dead idle will flat spot the cam. as far as the slobbering problem caused by incomplete fuel burning caused by low temps, try adding a cetane booster if you know you have to idle. raising the cetane level will help the fuel burn more effectivley. most of the fuel out here now is cetene deficient anyways. not sure if it will help but wont hurt for sure.