I'm not sure I entirely agree with the current discussion on aftermarket
add-on oil coolers.  I bought my '81 westy a year ago with an engine
which had been burned out from, among other things, overheating.  I
had the engine rebuilt, and the oil-cooler system added, with gauges
to monitor the situation.  My current set up does have the external
active fan, a total of 3 filters, lots of extra hoses, oil, etc., and
a supplementary switch on the dash to turn on the cooler fan if I for
any reason wish to AHEAD of the time it would kick on normally, which
is at I think somewhere between 180-185F or so.  If I see a bad traffic
situation, or it's warm outside, or I want to climb a hill, or turn on
the AC, I just reach out and flick the switch.  Whether I do this manually,
or whether the system turns on via thermostat (either way I can "hear"
it come on), I can immediately see a noticeable difference in the lowering
of the oil temperature on the gauge.

Since it's been in proper working order, I've never had a significant
problem overheating, even while climbing long, steep grades over
passes in warm weather with the air-conditioning turned on.  I've read
that adding one of these systems is supposed to extend the life of
your engine for up to 50-100%.  Since I only have about 8K miles on
the rebuild, I can't yet speak to that, but going on the advice of
others, I figured it was worth the try.

                                  ---------------- 
/martha rubin     <nrubin@s1.csuhayward.edu>
    '81 westy (puke-eggnog).  And no, it doesn't have a shower, toilet, hot
         water, laundry, or  dishwasher, but I'm working on it, cuz I'm
          not about to let Schwarzmeister beat me!  :)
    '80 bug convertible (stock triple-white)
    '73 or '74 Thing/Safare/Trekker/181 "wannabe."  If you hear of one in
         in need of a good home/restoration, etc., PUHLEEZE let me know!
                                  ----------------