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Garage => Mechanicals => Topic started by: chrismears on 22 November 2004, 11:04 PM

Title: sounds like steam
Post by: chrismears on 22 November 2004, 11:04 PM
I am trying to identify a sound from my engine bay.  It reminds me of escaping steam.  My car:

1980 300SD (w116/120)

The sound is mostly (if not only) noticeable at idle and does not dissappear as the engine warms.  I thought that it could be a bearing failing in something like a water pump, but nothing is getting warm to touch, and there appears to be no freeplay.

It doesn't have the high-pitched squeal of a loose belt.

It seems to be coming from the area around the air conditioner compressor (right hand side of engine if facing car).
Title: Re: sounds like steam
Post by: john skene on 30 December 2005, 03:57 AM
Cchrismears, could the sound be a vacuum leak? I believe the diesels have to use a vacuum pump to control the engine cut-off and the automatic transmission changes that the 'gas' engines tap off from the inlet manifold.