C32 Burning Smell from Engine

[calgonis]

Hiyas,

I have started to get a burning smell entering the cabin when the car is warm. I cant decide if it's rubbery or an oily smell but either way its not good. It usually lasts for no more than a minute and then clears. Car drives as per normal with no dash errors.

I have read a bit on the internet about it being possibly one of two problems both mentioning a burning smell in the cabin. The supercharger bearing being worn or the crank position sensor needing replacement.

Anyone with a C32 had a similar problem. I cannot deal with it right at the moment as I am moving house.

It started a few weeks ago but I had just presumed at first it was the car infront making the smell but now I realise its mine.

Andrew

 

[Swozza]

If its a worn supercharger bearing you can hear it. I had this issue with mine and its fairly cheap to get repaired.

Open your bonnet turn the engine on and listen for a cog scraping noise. Also with the engine off you can take the supercharger housing off at the front and manual rotate and listen out of the same noise.

 

[rothbury]

Hiyas,

I have started to get a burning smell entering the cabin when the car is warm. I cant decide if it's rubbery or an oily smell but either way its not good. It usually lasts for no more than a minute and then clears. Car drives as per normal with no dash errors.

I have read a bit on the internet about it being possibly one of two problems both mentioning a burning smell in the cabin. The supercharger bearing being worn or the crank position sensor needing replacement.

Anyone with a C32 had a similar problem. I cannot deal with it right at the moment as I am moving house.

It started a few weeks ago but I had just presumed at first it was the car infront making the smell but now I realise its mine.

Andrew

Funnily enough I've had that smell on a few occasions from my C250cdi B/E. Can't say it's worried me - just put it down to newness!

 

[EDZ649]

I had a plastic bag melted to the exhaust on my E55 once, every time it got hot the stink was awful, especially in stationary traffic. Worth having a look underneath.

 

[louisv6]

Hiyas,

I have started to get a burning smell entering the cabin when the car is warm. I cant decide if it's rubbery or an oily smell but either way its not good. It usually lasts for no more than a minute and then clears. Car drives as per normal with no dash errors.

I have read a bit on the internet about it being possibly one of two problems both mentioning a burning smell in the cabin. The supercharger bearing being worn or the crank position sensor needing replacement.

Anyone with a C32 had a similar problem. I cannot deal with it right at the moment as I am moving house.

It started a few weeks ago but I had just presumed at first it was the car infront making the smell but now I realise its mine.

Andrew

My C320 (which I think is sort of roughly the same engine without the supercharger?) had seeping rocker cover gaskets.

Oil (in tiny quantities) was leaking onto the exhaust manifold and causing a burning smell to enter the cabin.

Only takes a couple of minutes to burn off once the engine is warm, and after that you don't smell anything.

Fixed the rocker cover gaskets, and back to normal. Wasn't cheap, mind.

 

[dspaven]

Smoke and acrid smell from N/S front

Hiyas,

I have started to get a burning smell entering the cabin when the car is warm. I cant decide if it's rubbery or an oily smell but either way its not good. It usually lasts for no more than a minute and then clears. Car drives as per normal with no dash errors.

I have read a bit on the internet about it being possibly one of two problems both mentioning a burning smell in the cabin. The supercharger bearing being worn or the crank position sensor needing replacement.

Anyone with a C32 had a similar problem. I cannot deal with it right at the moment as I am moving house.

It started a few weeks ago but I had just presumed at first it was the car infront making the smell but now I realise its mine.

Andrew

After giving my W203 C180 Kompressor the beans in second gear today, I was stationary in traffic and saw smoke coming out of the N/S front of the bonnet. It smelt very acrid and not unlike burning plastic. This lasted for about 30 seconds, and I limped home (about 2 minutes away). On inspection, I couldn't see any visble signs of damage, and oil and coolant levels were fine. I let the car cool down before running it for a while and taking it for a test drive. I thought that there was a bit of mechanical noise coming from the front of the supercharger, but didn't think anything more about it as the car appeared to drive normally.

Having read the above post, I have the horrible feeling that the smoke and smell may have been the supercharger clutch bearing disintegrating. Can anyone provide a view on the likelihood of this being the cause, and if so, whether a cost -effective fix is available?

Thanks in anticipation,

 

[lynall]

As louis says i have also replaced rocker gaskets on wifes c320.

Easy enough to check, stone cold engine, engine switched off! look down the side of the engine and put your hands at the very back of the rocker cover and the oil runs down the back onto the exhaust downpipe.

Gaskets werent dear from merc iirc £20 the pair and less than an hour to replace the pair.

Wont be crank sensor causing a smell.

The rocker cover is two pieces the main body is sealed to cylinder head with a rubber gasket as above and the top piece of the cover is sealed to the main cover with a special silicone sealant.


Lynall

 

[mercbnz]

have a look for maybe a leak that might be burning it could be somthing small

 

[calgonis]

Thanks all.

Just to confirm this turned out to be leaking rocker cover gasket. Car has done 77k for anyone else with a similar problem.

Thankyou louisv6 for you post.

Andy

 

[Hammy]

Funnily enough I've had that smell on a few occasions from my C250cdi B/E. Can't say it's worried me - just put it down to newness!

I also get this from time to time from my C250CDi. I read somewhere that on Diesel Mercs its related to the Diesel Particulate Filter. Instead of clogging up as happens on some other cars, Mercs burn the trapped particulates when the filter fills up creating the burning smell from the exhaust.