From: Watson, t. on
On 1995 Buick Regal with 3.8 liter V-6 engine and two electric fans behind
the radiator, should both fans run at the same time when engine is hot? What
is the normal cycle of fan start-ups as the engine heats up?
Thanks!
tp94


From: Hachiroku ハチロク on
On Mon, 09 Aug 2010 18:15:39 -0700, Watson, t. wrote:

> On 1995 Buick Regal with 3.8 liter V-6 engine and two electric fans behind
> the radiator, should both fans run at the same time when engine is hot? What
> is the normal cycle of fan start-ups as the engine heats up?
> Thanks!
> tp94

I think on that car there is a main fan and then a secondary fan, the main
one comes on at a lower temperature.

The second fan may not come on at all unless the AC is switched on, then
they could both be running at the same time.

Next time it gets hot, turn off the AC and see if the fans are running. If
one is already running switch on the AC and see if the second one comes on.


From: Bill on
"Hachiroku ????" wrote in message
> On Mon, 09 Aug 2010 18:15:39 -0700, Watson, t. wrote:
>
>> On 1995 Buick Regal with 3.8 liter V-6 engine and two electric fans
>> behind
>> the radiator, should both fans run at the same time when engine is hot?
>> What
>> is the normal cycle of fan start-ups as the engine heats up?
>> Thanks!
>> tp94
>
> I think on that car there is a main fan and then a secondary fan, the main
> one comes on at a lower temperature.
>
> The second fan may not come on at all unless the AC is switched on, then
> they could both be running at the same time.
>
> Next time it gets hot, turn off the AC and see if the fans are running. If
> one is already running switch on the AC and see if the second one comes
> on.
>

On some cars, the second fan turns on with A/C on AND high side of A/C lines
pressure above about 220 psi. So may need to turn on the A/C and press on
the accelerator and it be a warm day to get the second fan to turn on.


From: Watson, t. on

"Hachiroku ????" <Trueno(a)e86.GTS> wrote in message
news:Pt38o.2015$st2.777(a)newsfe09.iad...
> On Mon, 09 Aug 2010 18:15:39 -0700, Watson, t. wrote:
>
>> On 1995 Buick Regal with 3.8 liter V-6 engine and two electric fans
>> behind
>> the radiator, should both fans run at the same time when engine is hot?
>> What
>> is the normal cycle of fan start-ups as the engine heats up?
>> Thanks!
>> tp94
>
> I think on that car there is a main fan and then a secondary fan, the main
> one comes on at a lower temperature.
>
> The second fan may not come on at all unless the AC is switched on, then
> they could both be running at the same time.
>
> Next time it gets hot, turn off the AC and see if the fans are running. If
> one is already running switch on the AC and see if the second one comes
> on.
>
>

Thanks very much for the answers! The second fan still does not run but
maybe the temp was too low today. It was only 62 degrees outside today when
I tried turning on the AC and the second fan did not start. Everything else
is fine so maybe I do not really have a problem.
tp94