[6pack] Electric cooling fan: pusher or puller?

[Robert Lang]

On Wed, 7 Jan 2009, steve bridge wrote:

> Is there an easy, reliable way to wire the system to let a person know if the
> fan has quit running? Without a mechanical fan, an electric only set-up could
> cost a lot of money and cause heartache.

There's a couple of ways to know the fan is running (or not).

First is the temp guage. That should be pretty obvious.

But there are shcematics "out there" on the internet that show how to wire 
in an indicator lamp for your fan that illuminates when the fan is running 
(or not, depending on how you wire it).

In contrast to your comment that an electric setup could cost a lot of $$$ 
and cause heartache, I'd say that roughly 8 HP gain for $200 is CHEAP. 
There really is no downside to the conversion other than the time it takes 
to install (a real mechaincal novice could do a fan installation in a 
couple of hours plus or minus, maybe longer if the radiator has never been 
out of the car).

But back to the point if your cooling system fails for any reason, there's 
usually a lot of steam or other indicator that things aren't working long 
before you'd ruin the motor from overheating. So in 50 words or less, I 
wouldn't equate an electric fan with hearthache and/or expense.

Ask yourself this one: when was the last time you saw a mechanical fan on 
a modern car? There's a reason why this is and it isn't just the cost. 
It's how the mechanical fan plays into available power, parasitic losses, 
mechanical efficiency and "stuff like that".

I converted 10 years ago. Haven't looked back since.

BTW, I rigged mine so it comes on when the key is on. There's no 
"electronics" to go bad. If that sort of setup doesn't float your boat, 
you can rig the fan to run via a simple switch and you can turn the fan on 
when the temp guage swings to the high side. Lo-tech, but it'll work. 
Actually, that's what I do with the race car. I don't like adding things 
that can fail on that car, 'cause they always fail when you don't want 
them to fail (or need a distraction).

:-)

regards,
rml
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