rattles on start up

[japimport]

hi there i havea c200 sport its a 95 nd it has 118,000 miles on it on start up a couple of times i can here a rattle from the engine bay forr about 3 seconds is this the sign of trouble ahead or is it normal thanks

 

[BlackC55]

It may just be the chain tensioner filling up. When was the last oil change?

 

[japimport]

i done an oil change 2 months ago with castrol magnetic

 

[jaymanek]

you need to get the chain & tensioner looked at before it snaps.

 

[japimport]

so you think its that serious? it doesnt happen all the time just the odd time do you think i could have a look myself is there anything i should look for

 

[jaymanek]

rattling on start up is the first sign of either a stretched chain or weak tensioner... either way, if left it could eat the engine.

 

[japimport]

will i have to leave it in to a mercedes garage then or is it easy enough to do

 

[230K]

Hi

Could it be something as simple as the hydraulic tappets? Once they get oil pressure they stop rattling/tapping?? Loads of cars have this trait.

230K

 

[Dieselman]

It needs listening to with an engine stethoscope or an experienced person may be able to tell the problem.

If it's hydraulic tappets then a flush with flushing oil may well help.

 

[japimport]

hi thanks for the replys when it is started up it happens for just to seconds then its gone and its only on some starts more so when its cold and not being driving in aday im hoping its not the timing chain or tensioner if it is would it be expensive im in dublin so what ever price its in uk itll be nearly double over here

 

[jaymanek]

is it a rattling or tapping??

 

[japimport]

it happens so quick the way id describe it it sounds like marbles in a tin can shook fast actualy more like a rattle snake

 

[rajinder_1]

Are you sure its coming from the engine and not the exhaust?

Raj

 

[recycled]

please have it looked at in the garage or a specialist. it costs nothing and it is catastrophic if it fails ( the chain that is)

 

[Dec]

Are you sure its coming from the engine and not the exhaust?

Raj

Would agree with Raj, there is a heat shield driver side of gearbox, on the exhaust, close to a bend, worth checking first. It can rust and rattle.

Dec

 

[japimport]

as rajinder was saying about the exhaust rattling sounds good to me but by all the replys its seems to be in favour of the timing chain/tensioner so does anyone know roughly this is going to cost me im praying its not to much as im just back from holiday and im smashed

 

[recycled]

it should cost you nothing for the diagnosis. as for fixing it (if that is the problem)varies. close to £200 or thereabouts.
if that is the problem and you do not, and it snaps, that is another engine needed

 

[japimport]

thanks everyone for the replys yous have being very helpfull as always ill keep yous posted on how i get on thanks again

 

[japimport]

up date on rattle on start up seen a mechanic today he had a listen around the engine and said it sounds ok i asked him about the timingchain etc he said it would be the timing chain if it was rattling all the time he then told me not to be panicking its nothing major the rattle on start up he then said if ts not broke dont fixit ?what do yous think of that

 

[jaymanek]

i think you need to take it to a better mechanic as you need to know exactly what the noise is before you make a decision on whether or not it needs rectifying..