Short rattle on start when cold - 2009 SLK280

[Muttlyoo7]

I have a 2009 facelift SLK280 which has a slight rattle on start when it's been sat for a long time. I thought it might be a timing chain/tensioner issue. However it has the later timing chain so is this likely? The car has a FSH and has just done 85,000 miles.

 

[oigle]

If stood for long period, oil will drain from tensioner so, until oil pressure builds up again, it can exhibit some rattle.

 

[Uncle Benz]

At 2009 you are past the chain sprocket wear point. Cam variators can rattle on start up, and the chain tensioner can still go weak. With the engine off and the oil cap removed put a bar on the crank pulley and inch the engine forwards and backwards while watching the chain in the oil filler hole. If there is any slack/delay in the change of direction it’s the tensioner gone weak. They have a device within which keeps them pushed tight while the oil pressure isn’t there and it wears out. A new one comes locked, and you release it by removing a cap on the left hand bank and hold the camshaft still with a tool while turning the crank pulley backwards. Once unlocked the spring within the tensioner is released and the chain is tensioned.

 

[mattkh]

The car has a FSH and has just done 85,000 miles.

What engine oil is in the engine..

 

[ajlsl600]

Try changing tensioner.. If that don't shut it up ur looking chain and maybe guides, hopefully ur sprockets are OK. If me I at tensioner 1st, usually easy enough unless Mr benz has become obstructive?

 

[Bay Leaf]

I had a slight rattle on my 2013 SL 350 32000 Mls when started after a period of time and sometimes when warm. I started using Shell Helix Ultra engine oil about three years ago, it hasn't rattled since. It has an additive called Tackifiers ( look it up on Google )

 

[Muttlyoo7]

What engine oil is in the engine..

It's just had a B service at MB Portsmouth. So I guess it's the MB oil 0W40.

 

[mattkh]

It's just had a B service at MB Portsmouth. So I guess it's the MB oil 0W40.

Thanks.
Check the invoice to see if they did a flush of the engine.
If not, then put a small can of Wynns Hydraulic Valve Lifter in the engine oil.

 

[oigle]

Thanks.
Check the invoice to see if they did a flush of the engine.
If not, then put a small can of Wynns Hydraulic Valve Lifter in the engine

Mmmm. People and their additives.........

 

[Bay Leaf]

Mmmm. People and their additives.........

If you are referring to my post about the Shell oil ( which you may not be ) but is rated as one of, if not the best oil on the market. It's now the go to oil for Ferrari.

 

[oigle]

If you are referring to my post about the Shell oil ( which you may not be ) but is rated as one of, if not the best oil on the market. It's now the go to oil for Ferrari.

No way. I love Shell oils. Always been good. The additive you mentioned was included by SHELL, not by someone who thought they knew better than SHELL