Very very loud Rattle on start up W168

[BIG Sean]

Advice required on what this might be - 2004 W168 1400 only done 45k was worked hard (full of camping gear) over to Yorkshire last week but was ok until this evening - restarted fifteen minutes after being warmed up fully and sounded like a tank

 

[BIG Sean]

Anyone??

 

[michael8554]

Bit too vague I expect.
Where is the noise coming from, top or bottom end of engine?
Blowing exhaust?
Alternator or water pump bearings gone?
Need some clues.

 

[grober]

If its a diesel-- dual mass flywheel??

 

[ringway]

Many moons ago I left my ford Sierra running and forgot to turn it off for around 3-4 hours. It was never the same after that.
Sounded like a skeleton have a w*nk in a biscuit tin.

 

[forrera]

if the rattle come on when you start it from cold only, just replace the hydraulic tensioner, easy job.
this happens to a140 more than any other w168.

 

[BIG Sean]

if the rattle come on when you start it from cold only, just replace the hydraulic tensioner, easy job.
this happens to a140 more than any other w168.

Thanks for this my mate has had it today and taken the alternator belt off to discount the water pump he thinks its either the chain or the tensioner. He's spoken to a merc mechanic who was a little cagey about how to do it. Is it possible without taking the engine out?

.....and sorry it's a 1400 petrol

And the sound is coming from low down in the engine it's deffo not a blowing exhaust

 

[BIG Sean]

Does Olly still frequent the forum? Would somebody please point him at this thread and ask if he would mind commenting - cant pm on the app

 

[forrera]

timing chain can be replaced without taking the engine out, I've done several of them.
A class is not every mechanics cup of tea. my garage is in London W6.
olso see facebook page https://www.facebook.com/aclassForrera

 

[BIG Sean]

That is good news unfortunately I'm over 200miles away. Would you mind telling me how?

 

[forrera]

I'll be adding pictures on facebook soon

 

[BIG Sean]

Is it a common problem?? To be fair it's been a really good car so far and she's had it for nine years without a problem - I'm not sure why the w168 A Class gets such bad press. The interior is a bit cheap and the difficulty of messing with the oily bits is a bit of PITA but other than that..........

 

[forrera]

you can see pictures on facebook now.

 

[BIG Sean]

you can see pictures on facebook now.

Thanks ill have a look

 

[BIG Sean]

Tensioner changed still sounds like a bag of spanners thrown against a wall - could we have valve damage???

 

[grober]

Post #4??

 

[BIG Sean]

It's a petrol not diesel

 

[BIG Sean]

Forrera/Olly

My mate has got it stripped down and we've determined that a full chain kit is the way to go - top sprocket is worn and the chain is shot.

Is it possible to replace the crankshaft sprocket with the engine in?

 

[forrera]

the engine must be taken out to access the crankshaft sprocket, and it might be cheaper to replace the whole engine in this case as you can buy them really cheap.

 

[BIG Sean]

the engine must be taken out to access the crankshaft sprocket, and it might be cheaper to replace the whole engine in this case as you can buy them really cheap.

How do you know the engine you are putting in is not going to go **** up too? This car has been driven for the last 9+ years by my wife she doesn't drive it hard - still can't understand why it has done this on just 45k - I had a c class that was on 160k when i had it three years ago and its still knocking about