How much amperage can an alternator support? no really...

[Mark J. Besso]

Vittorio,

I'm not a professional technician like John.  I'm also not one to experiment 
on everything like Cody.  I will say that I respect both their opinions very 
highly and know that they speak from first-hand experience.

My own first-hand experience with running the radiator fan on an Audi for 
racing was with a 4KQ that was used in rallying and hillclimb events. 
 Between the fact it got run in all seasons, sometimes at radically changing 
altitudes, it would occasionally require the fan to be run full-time.  I 
left the standard dual-stage thermoswitch in place and wired a switch to 
override it when I wanted.  I would generally switch it on a few minutes 
before the beginning of a stage (or just prior to a climb) and let it draw 
the temperature down below the 'normal' operating temp.  I'd shut it off 
when the stage/climb started and watch the temperature gauge occasionally. 
 I could manually cool the car to whatever temperature I preferred.

~Mark



On Wed, 6 Feb 2008 09:41:33 -0500
  "Vittorio Bares" <Vittorio.Bares at nuance.com> wrote:
  *This message was transferred with a trial version of CommuniGate(r)
Pro*
  
>> Um... no. The coolant thermostat will keep the engine at the stats 
>> design temp if it's in proper working order. Granted the engine 
>>should 
>> be allowed to run 10 or so degrees above stat temp, but with a 190 
>> degree stat the engine should run roughly at 190 degrees with the fan 
>> full on.
  
  Looks like there is consensus that a properly operating thermostat
will keep the engine running at the appropriate temp.
  
>> Now if it were my car the fan would be on an automatic fan switch 
>>with 
>> a manual over-ride. That way if it ever starts getting warm you can 
>> assume a switch failure and flick on the over-ride, voila good to go. 
>> Saying that a manual switch is removing a failure mode is very very 
>> faulty logic...the toggle switch used sure as hell isn't impervious 
>>to 
>> failure (in many cases it may be MORE likely to fail), which means 
>>you 
>> have deleted one failure point and added another, plus added 
>> additional wiring that could fail.
  
  Given that the entire car was re-wired - 'additional' wiring was
deleted ;)
  
  Your strategy, which would include a temp-switch w/a manual override
seems like the best approach - giving some level of redundancy. My
assumption is that a good switch should have a very good MTBF compared
to a temp switch - esp since its hardly used (switched to off, then
on) - but this may also be a bad assumption.
  
  Vittorio -
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