Slk 200

[Andlyn61]

Hi, just bought car from garage last week, its a 55 plate with 44,000 on the clock. When cold in the morning the engine or something under the bonnet rattles on start up. It sounds like the top end but not sure, it only last a couple of seconds - is this common or should I take it back to the garage as this is the first merc I have bought

 

[Sp!ke]

Sounds like noisy hydraulic valve lifters - how clean does your oil look and is it the right grade?

 

[Andlyn61]

Hi Sp!ke,

Wasnt sure if engine had hydraulic lifters as that was a thought, will check with garage as to grade used. Out of interest what grade should be used - 10/30 ?

Thanks for reply

 

[BTB 500]

Grade should be specified in the handbook.

 

[Andlyn61]

Hi,

Found spec - 0W/40 or 5W/40, fully synthetic

 

[Andlyn61]

Garage have put in semi synthetic 10W/40 oil in, this might explain noise

 

[Terry_]

Garage putting 10w40 in shouldnt make anything rattle on start up. Generally 5w40 is used nowadays in most petrol engine mercs although it doesnt have to be 5w40
A rattle on start up on a 271 engine could well be lifters, although they tend to tick more than rattle. I would be looking more towards a fault with the chain gear/ variators
Did you have the mileage varified? I would have a specialist look for you because if it is chain related it needs to be addressed before some thing goes wrong!

 

[Benza750]

Oil grade needs to be to mb spec mb 229.5. 5/40 should be used.
10/40 is ok but will need changing more regularly. If it rattled on start up its usually timing chain or tensioner related.
Get it checked as this engine is prone to timing chain jumping & or stretching

 

[Andlyn61]

thanks for all the advice guys