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Discussion Starter #1
For the last few weeks I've been getting an erratic rustling sound. It sounds like it's under the bonnet to the right and forward of the driver's position. (I'm in the UK, right-hand drive). It starts well after the temp gauge has settled on its usual 85deg. When I stop driving to have a look, sod's law, the noise stops. The engine is very hot but dry. It DOES sound like a spluttering/"rustling leaves" sound. It's a bit variable, but I think I can sometimes get the noise to stop by turning up my interior fan and heating very high. Previous to a few weeks ago, the jubilee clip that holds the radiator hose on had been thrown off 3 or 4 times on the open road, resulting in an empty radiator. I now have a very tight clip that has stayed put. I've checked water level as per the manual, so it just covers the visible surface of the expansion chamber when cold. But the day after the funny noises, when I open the radiator filler cap, there's a loud escape of air, and sometimes some coolant bubbles up and out of the neck too. Don't know if these symptoms are relevant to the noises, but I suspect so. I wouldn't say it's losing much water/coolant, maybe just a very little. Any suggestions or help would be much appreciated. If using technical terms, please also use noddy terms, so I can follow you. (There might be a short delay while I find someone who can help me test any ideas.)Many thanks in advance.
 

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got same model...they make noises..especially if they've done high milage..you could try any number of things..or turn the radio up! Try one at a time...and then run it.Don't worry too much..just make sure its oil is changed reg and serviced...to be honest there is not a great deal of things that will stop the vito 108d....you could try the fan unit,mine made a similar sound and i changed the whole motor, and impt got rid orf the pollen filter...lets in more air and heat!!Good luck...maybe you got a mouse livin in there1[8)][:eek:)]
 

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Discussion Starter #4
Thanks. No, but I'll ask someone if that's a possibility.

My garage suspects a 'small blow' through the cylinder-head gasket. The clue being that there's a release of pressure when you open the coolant filler cap the day after, when the engine's cold. He thinks the noise could be an airlock-type noise in the highest point of the cooling system, in the hose.
 

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My 110CDI makes noises in that area too.
Also, sometimes, the belt squeals with the AC on.
Guru, where is the tensioner shock absorber?
I actually had the tensioner assembly changed (I think it has a spring inside, dunno).
Is there a seperate shock absorber?

Thanks,
Philip
 

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Signs of bubbles in the expansion tank is indeed head gasket on the way out but this may not be related to your noise problem which appears to be some other problem. Is the rustling sound there when engine is at idle?
 

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ML63 AMG & 2 350 SLK with AMG kit.
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Hi, The noise is probably water running around the engine cooling houses, the heater houses etc.
you need to fill the expansion tank and squeeze the tubes to push the air out. start the engine and run it until hot, then let it cool before fitting the expansion cap. this will ensure the air has escaped.
If bubbles are found in the expansion tank it is a sign the head gasket has gone, but before condemning it try the fill process above. This will make the thermostats open and fill the tubes with coolant.
don’t forget antifreeze
Ian.
 

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Discussion Starter #8
Sorry to say the cause was indeed a 'blown' cylinder head gasket. The occurrence of the radiator pressure build-up/coolant light coming on/radiator hose jubilee clip thrown off/rustling noises/delete-as-applicable problems eventually became as frequent as every 10 minutes. The gasket has been replaced (I saw the charring on the old one) and everything is fine, and the van is much nippier.
 

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