AC compressor oddity

["Sacha Prins" <sacha@xxxx>]

Hi,

I have a very small, yet annoying problem with my AC compressor. First
off, everything works, I recently bought the car (#16187) and it had
been sitting still for approx. 8 years. But pressure testing the AC
went well, and after filing it it worked.

However, every time the AC compressor 'kicks in', which is every
couple of seconds, I hear a grinding/buzzing sound that resonates
through the entire car, and my perception is that when I drive 25MPH
the car slows down a bit (fractionally) when this happens. Almost as
if the AC compressor slows the engine (by 'braking' the engine through
the belt). The AC belt also 'wiggles' more when the AC compressor is
active, which tells me that there is some (if not a lot) of resistance
on that belt when the compressor is active. I already tried to tighten
the belt to no avail. I'll try to tighten it again one of these days,
but something tells me that there is something else wrong.

The wheels that guide the belt seem to turn OK, and I lubricated the
guide-wheels and the moving parts of the compressor with WD40, but
that doesn't help.

What's more, the resonating sound seems to come from the front of the
car, and when I put my ear over the opened engine cover the sound
doesn't seem to come from the compressor.

I have absolutely no idea where to look, so if someone (from this
fuzzy description) can point my in any direction I'll be much obliged.

Thanks,

Sacha