The fans do make a lot of noise when going into high speed. Dirt or wear on
the blades or worn bearings add to the commotion. The point that you are
really missing is the low speed is not working. The high speed is there as a
stop gap emergency oh my gosh the coolant is too hot and the fan needs more
help or the AC high side pressure is too high and it needs more help. You
will need to some electrical trouble shooting. Most likely the speed
resistor behind the drivers side headlamp is burned out.

Dennis

>From: Jeff Michal <jeffmichal@YAHOO.COM>
>Reply-To: Jeff Michal <jeffmichal@YAHOO.COM>
>To: vanagon@GERRY.VANAGON.COM
>Subject: Horrendous Noise - Radiator Fan
>Date: Tue, 19 Jun 2007 09:56:11 -0700
>
>Hello.  I was riding around in my van (90 GL) yesterday and all the sudden
>the cooling fan trips on while I am sat at a light.  This has happened
>before, but what was outside of normal was that the fan was making a huge
>amount of vibration that pretty much shook the whole van till it got the
>engine temp down and cut off.  I figure something is hitting the fan blade
>or maybe a mounting screw came loose.  My daily drive isnt very long and
>generally the cooling fan doesnt come on during the drive.  I am hoping
>someone can tell me the best way to get in there to look and see what is
>afoot.  I looked into the front end, but I can see the radiator is in the
>way.  What is the best way to get to this fan to investigate the problem?
>
>Thanks,
>
>Jeff
>90 GL
>
>
>
>____________________________________________________________________________________
>Fussy? Opinionated? Impossible to please? Perfect.  Join Yahoo!'s user
>panel and lay it on us.
>http://surveylink.yahoo.com/gmrs/yahoo_panel_invite.asp?a=7