I have something similar - I am told is is a bearing screaming.

Of course, a "cold engine" is relative - mine only does it at about -15 C
and below.

Marshall Ruskin

>Just wondering if anyone knows this sound.
>Lately everytime I start up the van, and the engine
>is cold, it sounds like a cow mooing coming out of
>the engine compartment.
>Sort of like this. Moooooo.....
>It only does it at about 1500 rpms, and then after
>a few minutes it goes away.
>Maybe I should buy some hay.
>Harald
>'90 westy
>