Switch ID

[Dave Plowman (News)]

You mean before the days of thermostatic viscous couplings?

BTW, that 50 amps you claim an electric fan takes is more than twice the output of the generator on many 60s cars.

[Dave Plowman (News)]

Had that on my BMW 20 years ago. It also kept the fresh air vents closed until the cabin heated up. Also had an aux electric water pump so you could use the heater with the engine stopped. Until the coolant dropped below a set temperature.

[charles]

and so is the 200A starting current - that's why a car has a battery

[The Natural Philosopher]

Of course not. They were power sapping monstrosities. If good enough to cool at a tickover a waste of fuel and power at cruise. Even te viscous coupling monstrosities were abandoned IIRC.

Prezactly., And its a strange fact, electrics got cheaper than mechanicals. Once you HAVE an ECU etc why not throw in sensors and control a fan set from it?

Electric windows are apparently cheaper than the winddown sort, too.

[Muddymike]

My engine was fitted with a viscous driven mechanical fan. I converted to electric so that I can switch it off when in deep water. Rover V8 petrol engines don't run well when being sprayed a mass of with water!

Mike

[Max Demian]

They had a thermostat to restrict the water flow until the engine warmed up. And if that failed you stuck foil over the radiator grill in the winter (Mk 1 Escort).

[Dave Plowman (News)]

You run your starter motor for long periods? A cooling fan can do just that on a hot day in slow moving traffic.

[tony sayer]

Yes cheaper but have you seen the replacement cost of some electric's these days like ECU's?, makers got us over a barrel;(...

[charles]

The 50 A quoted was "startibg current" not running current

[Capitol]

Or use a radiator blind.

[Capitol]

Seems unlikely even as a starting current, the series resistance would limit it.

[The Natural Philosopher]

I would expect a decent fan to be starting at at least that if not more

12V/20A is not a huge amount of power for a fan.

It will fly a couple of pounds of model plane with some authority though.

[The Natural Philosopher]

ROFLMAO!

0.1 ohms or less won't limit much, and that's only a crappy 200W can motors...

Decent 200W motors will have resistances sub 20 milliohm

[Dave Plowman (News)]

Turnip hasn't a clue as usual. The amount of power a fan consumes when the car is stationary bears no relation to the amount of power it takes with airflow through the rad when the car is moving. And since it pulls air through the rad, will also tend to pull the car along.

But most have decent cars have had thermostatically controlled viscous couplings for perhaps 30 years or so. Which allows the fan to idle round when not needed. Indeed, many hardly ever transmit the full drive to the fan.

[Dave Plowman (News)]

It's still bollocks. A fan isn't stalled or under high load when it starts. And doesn't have a series wound motor.

[charles]

I added one of those to my Cortina pre-1984, probably in the 1970s.

[Dave Plowman (News)]

Not sure when the thermostatic ones came in - but generally aren't an easy update. The waterpump fixing is very different.

[DerbyBorn]

Harry Bloomfield wrote in news:ocja6t$lfn$ [e-mail]:

The metal fabricated fans were crude and inneficient. Why on earth didn't they make them from plastic.

[dennis]

Pressed metal was cheap as was the tooling. Injection moulding was expensive with tools big enough. Now with automated machines the moulds cost not a lot.

[Bob Minchin]

Are you still looking for switches Mike?

I found some likely looking candidates here

I did not look in full detail but most seemed to have screw terminals rather than lucar spades but I guess you could work round that.

Bob