Overheating

Tim McNamara wrote:
> My 1990 240 overheated yesterday, the needle just climbing to the bottom
> of the red zone on the temp gauge in stop and go traffic. On the
> highway at 60 mph the temp would drop down almost to normal. When I got
> home I looked under the hood and saw indications of boiling coolant in
> the overflow reservoir. The car ran just fine. Coolant level is at the
> minimum mark on the tank.
>
> It's been running just a bit warm when the air temps is above 80F. My
> guess is plugged up radiator. Goes into the shop Monday AM.


Sounds like the fan clutch to me, I've also seen this on mine when the
wire came off the switch for the electric aux fan on the front, I'm not
sure if the non-turbo cars have that though.
 >> Stay informed about: Overheating 

migh be a failed cap on the coolant tank also...drop by your local
volvo shop
and have them pressure test it w/the proper tool...if it won't hold
the pressure...the
coolant will "blow" out of the system....The coolant system depends on
a certain pressure level......This happined on my s80 last month...$5
cap...
replaced...all is well....





On Jun 22, 1:13 am, James Sweet <jamesswe....RemoveThis@trashmail.net> wrote:
> Tim McNamara wrote:
> > My 1990 240 overheated yesterday, the needle just climbing to the bottom
> > of the red zone on the temp gauge in stop and go traffic.  On the
> > highway at 60 mph the temp would drop down almost to normal.  When I got
> > home I looked under the hood and saw indications of boiling coolant in
> > the overflow reservoir.  The car ran just fine.  Coolant level is at the
> > minimum mark on the tank.
>
> > It's been running just a bit warm when the air temps is above 80F.  My
> > guess is plugged up radiator.  Goes into the shop Monday AM.
>
> Sounds like the fan clutch to me, I've also seen this on mine when the
> wire came off the switch for the electric aux fan on the front, I'm not
> sure if the non-turbo cars have that though.
 >> Stay informed about: Overheating 

In article <57m7k.3975$i5.1360@trndny07>,
Bill Bradley <senatorREMOVETHIS RemoveThis @stargate.net> wrote:

> Tim McNamara wrote:
> > My 1990 240 overheated yesterday, the needle just climbing to the
> > bottom of the red zone on the temp gauge in stop and go traffic.
> > On the highway at 60 mph the temp would drop down almost to normal.
> > When I got home I looked under the hood and saw indications of
> > boiling coolant in the overflow reservoir. The car ran just fine.
> > Coolant level is at the minimum mark on the tank.
> >
> > It's been running just a bit warm when the air temps is above 80F.
> > My guess is plugged up radiator. Goes into the shop Monday AM.
>
> It could also be a failed fan clutch. The fan is supposed to
> freewheel when cold and engage when hot. I'm not sure whether they
> used the bimetallic strip or the fluid-type clutch on a 1990, but
> both are known to fail.

Ah. Something else to consider and would be in keeping with having
decent cooling at highway speed and poor cooling in stop-and-go traffic.

What would be the effect of this on mileage? I've been getting great
mileage lately.

I'd pondered installing an electronic fan conversion a few times in the
past, hoping to improve mileage and responsiveness. Is this a
worthwhile conversion? If so, I might just go that route if it's the
fan clutch that's shot.
 >> Stay informed about: Overheating 

In article <lYm7k.286$zE6.120@trnddc02>,
James Sweet <jamessweet1.RemoveThis@trashmail.net> wrote:

> Tim McNamara wrote:
> > My 1990 240 overheated yesterday, the needle just climbing to the
> > bottom of the red zone on the temp gauge in stop and go traffic.
> > On the highway at 60 mph the temp would drop down almost to normal.
> > When I got home I looked under the hood and saw indications of
> > boiling coolant in the overflow reservoir. The car ran just fine.
> > Coolant level is at the minimum mark on the tank.
> >
> > It's been running just a bit warm when the air temps is above 80F.
> > My guess is plugged up radiator. Goes into the shop Monday AM.
>
>
> Sounds like the fan clutch to me, I've also seen this on mine when
> the wire came off the switch for the electric aux fan on the front,
> I'm not sure if the non-turbo cars have that though.

No auxiliary fan on my car.
 >> Stay informed about: Overheating 

Sticking thermostat?
 >> Stay informed about: Overheating 

On Jun 22, 2:16 am, Bill Bradley <senatorREMOVET... DeleteThis @stargate.net>
wrote:
> Tim McNamara wrote:
> > My 1990 240 overheated yesterday, the needle just climbing to the bottom
> > of the red zone on the temp gauge in stop and go traffic.  On the
> > highway at 60 mph the temp would drop down almost to normal.  When I got
> > home I looked under the hood and saw indications of boiling coolant in
> > the overflow reservoir.  The car ran just fine.  Coolant level is at the
> > minimum mark on the tank.
>
> > It's been running just a bit warm when the air temps is above 80F.  My
> > guess is plugged up radiator.  Goes into the shop Monday AM.
>
>         It could also be a failed fan clutch.  The fan is supposed to freewheel
> when cold and engage when hot.  I'm not sure whether they used the
> bimetallic strip or the fluid-type clutch on a 1990, but both are known
> to fail.
>
>         Bill

yeah; bum radiator would be opposite, overheats on the highway, cools
off when idling.
 >> Stay informed about: Overheating 

On Jun 22, 12:17 am, Tim McNamara <tim....DeleteThis@bitstream.net> wrote:
> My 1990 240 overheated yesterday, the needle just climbing to the bottom
> of the red zone on the temp gauge in stop and go traffic.  On the
> highway at 60 mph the temp would drop down almost to normal.  When I got
> home I looked under the hood and saw indications of boiling coolant in
> the overflow reservoir.  The car ran just fine.  Coolant level is at the
> minimum mark on the tank.
>
> It's been running just a bit warm when the air temps is above 80F.  My
> guess is plugged up radiator.  Goes into the shop Monday AM.

My guess is a failed fan clutch.
 >> Stay informed about: Overheating 

Well, the mechanic checked it out and flushed the system, checked the
radiator, checked for pressure leaks, replaced the thermostat and
replaced the temp gauge sender as that's has always functioned rather
intermittently. It stayed in the normal range on the highway, in stop
and go traffic and while idling for the mechanic. I'll give it a good
run tomorrow.
 >> Stay informed about: Overheating 

On Jun 23, 7:55 pm, Tim McNamara <tim... RemoveThis @bitstream.net> wrote:
> Well, the mechanic checked it out and flushed the system, checked the
> radiator, checked for pressure leaks, replaced the thermostat and
> replaced the temp gauge sender as that's has always functioned rather
> intermittently.  It stayed in the normal range on the highway, in stop
> and go traffic and while idling for the mechanic.  I'll give it a good
> run tomorrow.

that mystery temp gauge board on back of the instrument panel can be
suspect too. sometimes even just the connections to it. when it goes
bad, you see huge temp guage swings at unrealistic rates of change but
the cooling system doesn't seem overheated.
 >> Stay informed about: Overheating 

In article
<917f3a1c-ae23-42b8-a0f5-43aef8bf00e4.DeleteThis@m36g2000hse.googlegroups.com>,
z <gzuckier.DeleteThis@snail-mail.net> wrote:

> On Jun 23, 7:55 pm, Tim McNamara <tim....DeleteThis@bitstream.net> wrote:
> > Well, the mechanic checked it out and flushed the system, checked
> > the radiator, checked for pressure leaks, replaced the thermostat
> > and replaced the temp gauge sender as that's has always functioned
> > rather intermittently.  It stayed in the normal range on the
> > highway, in stop and go traffic and while idling for the mechanic.
> >  I'll give it a good run tomorrow.
>
> that mystery temp gauge board on back of the instrument panel can be
> suspect too. sometimes even just the connections to it. when it goes
> bad, you see huge temp guage swings at unrealistic rates of change
> but the cooling system doesn't seem overheated.

With the old sender, the gauge tended to not work if the air temperature
was above about 55F- the needle just stayed at the bottom. Once in a
while it would come to life, such as in the recent overheating scenario.
In the winter it seemed to work fine. Today with new sender, I saw some
of what you are describing. The car ran like a top.
 >> Stay informed about: Overheating