Re: fan troubles

[knut.s.grimsrud@xxxx]

It sounds like the issue you are referring to is that your fans seem 
to be running longer than expected once they kick on

I had this same isse with one of my cars,and the cause in my case was 
quite simple. The otterstat has some hysteresis built into it so that 
it activates at one temperature and deactivates at a lower 
temperature (the otterstat is just a thermal switch). In my case, my 
symptoms were that once the cooling fans turned on they would stay 
running until I turned the car off.

For me the source of the problem was merely that the thermostat and 
the otterstat had temperature ratings that were not quite compatible. 
The otterstat would trigger once the temperature got to about a 
needlewidth above the white tick mark halfway between the 100 and 220 
marks on the temperature gauge, and the otterstat hysteresis would 
keep the fans engaged until the temperature got to slightly below the 
tick mark. Unfortunately, the thermostat was such that it would never 
let the temperature get below the tick mark because that was it's set 
point. The result was that once the termperature rose to a 
needlewidth above the tick mark, the fans would come on and stay on 
until the temperature dropped to a hair below the tick mark which 
would never happen until the car was turned off. The fix in my case 
was to replace the thermostat.

On both of my cars, the fans come on about a needle width above the 
tick mark halfway between the 100 and 220 mark, and the fans stay on 
until the temperature drops to about the tick mark (or a hair below).

Knut


--- In dmcnews@xxxx, Delorean17@xxxx wrote:
> Hello, 
> When my fans come on they stay on for a Long time and rarely 
turn off. 
> They turn on exactly on the line below the 220 mark.

<snip>