JACKC141FE

Hi all I need some help, on my c280 103k miles, when its cold the engine knocks for a few seconds when started. Can the oil be draining down from the oil filter causing a zero oil pressure dry start? Is there a oil drain back valve in the system that may have failed?
Thanks Jack

Untertürkheim

You mean lifter noise?

What kind of oil and filter are you using?

vinceC

My 2000 with 126K has done this since I bought it with 60K. Since it was under an M-B extended warranty I had the dealer check it out several times. When I finally was able to talk to the Shop Foremen he told me it is carbon buildup on the top of the pistons. The M112 V-6 has very small clearances and is somewhat prone to this problem. He recommeded adding a cleaner like Techron every 5K or so. It seems to help on mine - the knocking is considerable reduced.

JACKC141FE

Using Mobil 1 Syn 10/30 and the standard MB that goes in the top of the v6 engine

JACKC141FE

Thanks i will give it a try.

Untertürkheim

That is the wrong oil, it is not MB approved. It, along with carbon buildup can cause the valve noise.

vinceC

I don't think the OP is talking about valve noise. The noise I have experienced, and I believe the OP is describing is a distinct knock - it sounds more like piston slap or even a rod knock.

Mobil 1 0-40 or 5W-40 is the currect spec for this engine.

Untertürkheim

Not mobil 1 5w-40.

Untertürkheim

There is some good information here: https://mbworld.org/forums/c-class-w204/268500-bring-your-own-oil-service-save-ok-what-type-quantity-should-i-bring.html#post3156412

xvvvz

From what I have read, it could also be a pulley bearing going bad or a tensioner going bad. I am dealing with a quick bit of knocking sound at startup and have read about many different causes, so it may not be a simple diagnosis. You need to experiment more and give us a more detailed description.

vinceC

An MBUSA update issued to dealers on June 5, 2006 instructs dealers to draw down their stocks of 0W-40 in preparation for a change to ESP Formula 5W-40. In the FAQ section the bulletin states that the new specification MB 229.51 is a universal oil that can be used in both diesel and gasoline engines. It goes on the state that while the 5W-40 is under study for AMG models, the dealers should continue to use 0W-40 in those models. It goes on the state the 0W-40 will not meet MB 229.51 specs. It also states that 5W-40 is backwards compatible with 0W-40.

The only place I can find ESP 5W-40 is the dealer. I still use 0W-40, but it is getting hard to find locally, and not due to the hurricane driven shortage. It just doesn't sell well locally so all the stores have reduced stock and I have to order it. My dealer price on ESP 5W-40 is competitive so I will probably have to switch soon for convenience sake.

Untertürkheim

It is better to avoid low SAPS oils unless required by your car. the -1 spec oils are not a further generation, so it is not a question of backward-compatability. Stick with 229.5, it is far better for the engine.

vinceC

Interesting note: The September 2006 issue of Factory Service Products listed 229.51 oils for both gas and diesel cars. The 2007 issue contains a notation that 229.51 oils are for diesels only.

So I stand corrected.

I have attached the latest issue for your information.

Untertürkheim

How do you come about those PDFs? I would like to see the latest release, I would imagine there have been updates since 2007.

vinceC

Untertürkheim

The August 2007 issue is the latest release. I get them from the Startekinfo website. It is part of the free information available on the site. I have attached a screen shot showing where it is located on the site.

Untertürkheim

Many thanks! Great information.