Dear Listers,

I noticed that the coolant was low, so I added to the reservoir, started
the engine, left the cap off and went to do something else, while the
engine was warming up. I come back to see that the overflow reservoir is
boiling happily away. So, I shut the engine down, replaced the cap and
restarted the engine and left to go finish something else.

When I came back steam/vapor was coming from the air vents, so selected
a higher setting for the fan. It blew the vapor away temporarily, but I
could see vapor still coming out of the side vents of the dash, where it
goes into the door panel. (The driver's door was open). I shut the fan
down and the vapor came seeping back through all the vents and it was
quite hot.

The ambient temperature was about 20 C (68 F) and the thermostat setting
was on 72 degrees and the A/C compressor switch was off and the
recirculation toggle switch was off. (Light was not on and fresh air was
coming in).

What gives? Can I drive this car without the cooling system blowing up?

Thanks for any advice....

pkallis wrote:
> Dear Listers,
>
> I noticed that the coolant was low, so I added to the reservoir, started
> the engine, left the cap off and went to do something else, while the
> engine was warming up. I come back to see that the overflow reservoir is
> boiling happily away. So, I shut the engine down, replaced the cap and
> restarted the engine and left to go finish something else.
>
> When I came back steam/vapor was coming from the air vents, so selected
> a higher setting for the fan. It blew the vapor away temporarily, but I
> could see vapor still coming out of the side vents of the dash, where it
> goes into the door panel. (The driver's door was open). I shut the fan
> down and the vapor came seeping back through all the vents and it was
> quite hot.
>
> The ambient temperature was about 20 C (68 F) and the thermostat setting
> was on 72 degrees and the A/C compressor switch was off and the
> recirculation toggle switch was off. (Light was not on and fresh air was
> coming in).
>
> What gives? Can I drive this car without the cooling system blowing up?
>
> Thanks for any advice....


Your heater core has failed, you'll have to get that replaced before it
makes a real mess. It probably won't blow up, but it will leak coolant
into your interior and it's not good for you to breathe the vapor either.

"pkallis" <pkallis@ameritech.net> wrote in message
news:x8dWg.10800$e66.9809@newssvr13.news.prodigy.c om...
> Dear Listers,
>
> I noticed that the coolant was low, so I added to the reservoir, started
> the engine, left the cap off and went to do something else, while the
> engine was warming up. I come back to see that the overflow reservoir is
> boiling happily away. So, I shut the engine down, replaced the cap and
> restarted the engine and left to go finish something else.
>
> When I came back steam/vapor was coming from the air vents, so selected a
> higher setting for the fan. It blew the vapor away temporarily, but I
> could see vapor still coming out of the side vents of the dash, where it
> goes into the door panel. (The driver's door was open). I shut the fan
> down and the vapor came seeping back through all the vents and it was
> quite hot.
>
> The ambient temperature was about 20 C (68 F) and the thermostat setting
> was on 72 degrees and the A/C compressor switch was off and the
> recirculation toggle switch was off. (Light was not on and fresh air was
> coming in).
>
> What gives? Can I drive this car without the cooling system blowing up?
>
> Thanks for any advice....

As James says, the heater core has failed... the symptoms are unmistakable.
(I'm assuming the vapor had the sweetish odor of antifreeze.) Unfastening
the heater hoses and plugging them will allow you to drive it until you can
get the heater core replaced if there will be a long lead time, but then you
will have no heat and no defroster.

If you drive the way it is you risk warping the cylinder head.

Mike

Hmmm.... sounds like bad news. Any ideas of what this would cost me to
replace?

Michael Pardee wrote:

>"pkallis" <pkallis@ameritech.net> wrote in message
>news:x8dWg.10800$e66.9809@newssvr13.news.prodigy. com...
>
>
>>Dear Listers,
>>
>>I noticed that the coolant was low, so I added to the reservoir, started
>>the engine, left the cap off and went to do something else, while the
>>engine was warming up. I come back to see that the overflow reservoir is
>>boiling happily away. So, I shut the engine down, replaced the cap and
>>restarted the engine and left to go finish something else.
>>
>>When I came back steam/vapor was coming from the air vents, so selected a
>>higher setting for the fan. It blew the vapor away temporarily, but I
>>could see vapor still coming out of the side vents of the dash, where it
>>goes into the door panel. (The driver's door was open). I shut the fan
>>down and the vapor came seeping back through all the vents and it was
>>quite hot.
>>
>>The ambient temperature was about 20 C (68 F) and the thermostat setting
>>was on 72 degrees and the A/C compressor switch was off and the
>>recirculation toggle switch was off. (Light was not on and fresh air was
>>coming in).
>>
>>What gives? Can I drive this car without the cooling system blowing up?
>>
>>Thanks for any advice....
>>
>>
>
>As James says, the heater core has failed... the symptoms are unmistakable.
>(I'm assuming the vapor had the sweetish odor of antifreeze.) Unfastening
>the heater hoses and plugging them will allow you to drive it until you can
>get the heater core replaced if there will be a long lead time, but then you
>will have no heat and no defroster.
>
>If you drive the way it is you risk warping the cylinder head.
>
>Mike
>
>
>
>

Replace the thermostat and ect sensor below the t-stat also.
Water should not be boiling out of the coolant bottle,
even with the coolant cap removed.
The electric cooling fan should have turned on instead.
The coolant boiling out in probablly due to a stuck closed t-stat.
The extra water pressure could have caused the heater core 2 fail and
start leaking.
The heater core is probably $300 to $400 and about
1hr to 1.5 hours labor.
You can not plug off the heater hoses.
The hoses have quick release fitting on them.
The one hose is pressurized anyway.
BD
"pkallis" <pkallis@ameritech.net> wrote in message
news:x8dWg.10800$e66.9809@newssvr13.news.prodigy.c om...
> Dear Listers,
>
> I noticed that the coolant was low, so I added to the reservoir, started
> the engine, left the cap off and went to do something else, while the
> engine was warming up. I come back to see that the overflow reservoir is
> boiling happily away. So, I shut the engine down, replaced the cap and
> restarted the engine and left to go finish something else.
>
> When I came back steam/vapor was coming from the air vents, so selected a
> higher setting for the fan. It blew the vapor away temporarily, but I
> could see vapor still coming out of the side vents of the dash, where it
> goes into the door panel. (The driver's door was open). I shut the fan
> down and the vapor came seeping back through all the vents and it was
> quite hot.
>
> The ambient temperature was about 20 C (68 F) and the thermostat setting
> was on 72 degrees and the A/C compressor switch was off and the
> recirculation toggle switch was off. (Light was not on and fresh air was
> coming in).
>
> What gives? Can I drive this car without the cooling system blowing up?
>
> Thanks for any advice....

Thanks for your reply. Good analysis.

Big Dick wrote:

>Replace the thermostat and ect sensor below the t-stat also.
>Water should not be boiling out of the coolant bottle,
>even with the coolant cap removed.
>The electric cooling fan should have turned on instead.
>The coolant boiling out in probablly due to a stuck closed t-stat.
>The extra water pressure could have caused the heater core 2 fail and
>start leaking.
>The heater core is probably $300 to $400 and about
>1hr to 1.5 hours labor.
>You can not plug off the heater hoses.
>The hoses have quick release fitting on them.
>The one hose is pressurized anyway.
>BD
>"pkallis" <pkallis@ameritech.net> wrote in message
>news:x8dWg.10800$e66.9809@newssvr13.news.prodigy. com...
>
>
>>Dear Listers,
>>
>>I noticed that the coolant was low, so I added to the reservoir, started
>>the engine, left the cap off and went to do something else, while the
>>engine was warming up. I come back to see that the overflow reservoir is
>>boiling happily away. So, I shut the engine down, replaced the cap and
>>restarted the engine and left to go finish something else.
>>
>>When I came back steam/vapor was coming from the air vents, so selected a
>>higher setting for the fan. It blew the vapor away temporarily, but I
>>could see vapor still coming out of the side vents of the dash, where it
>>goes into the door panel. (The driver's door was open). I shut the fan
>>down and the vapor came seeping back through all the vents and it was
>>quite hot.
>>
>>The ambient temperature was about 20 C (68 F) and the thermostat setting
>>was on 72 degrees and the A/C compressor switch was off and the
>>recirculation toggle switch was off. (Light was not on and fresh air was
>>coming in).
>>
>>What gives? Can I drive this car without the cooling system blowing up?
>>
>>Thanks for any advice....
>>
>>
>
>
>
>

pkallis wrote:
> Hmmm.... sounds like bad news. Any ideas of what this would cost me to
> replace?
>


Depends, the part is $171 online, the job is quite labor intensive
though, figure 4-6 hours of shop time. Seems like I've heard it quoted
at $600-$800 to have it done at an independent shop but you'll want to
call and find out. If you're a reasonably capable home mechanic you can
do it yourself but in most cars essentially the entire dashboard has to
be removed.

James Sweet wrote:
> pkallis wrote:
>> Hmmm.... sounds like bad news. Any ideas of what this would cost me to
>> replace?
>>
>
>
> Depends, the part is $171 online, the job is quite labor intensive
> though, figure 4-6 hours of shop time. Seems like I've heard it quoted
> at $600-$800 to have it done at an independent shop but you'll want to
> call and find out. If you're a reasonably capable home mechanic you can
> do it yourself but in most cars essentially the entire dashboard has to
> be removed.
Anything more then 3 Hours labor then find another repair shop the
dashboard does not have to come out to do the heater core
Glenn

--
"*-344-*Never Forgotten"
Is for the New York City Firemen who lost their lives on September 11,2001.
The official count is 343, but there was also a volunteer who lost his life
aiding in the initial rescue efforts. And I will never forget them as
long as I live,
nor should any American.

Glenn wrote:
> James Sweet wrote:
>
>> pkallis wrote:
>>
>>> Hmmm.... sounds like bad news. Any ideas of what this would cost me
>>> to replace?
>>>
>>
>>
>> Depends, the part is $171 online, the job is quite labor intensive
>> though, figure 4-6 hours of shop time. Seems like I've heard it quoted
>> at $600-$800 to have it done at an independent shop but you'll want to
>> call and find out. If you're a reasonably capable home mechanic you
>> can do it yourself but in most cars essentially the entire dashboard
>> has to be removed.
>
> Anything more then 3 Hours labor then find another repair shop the
> dashboard does not have to come out to do the heater core
> Glenn
>


I guess they improved that on the 850? I know a heater core on a 240 is
a *major* job, having spent the better part of a day on one. Thankfully
I haven't had to find out on any newer cars yet but it doesn't look real
easy to get to on my 740 either.

"James Sweet" <jamessweet@hotmail.com> wrote in message
news:CfCWg.6070$K11.3233@trndny07...

> I guess they improved that on the 850? I know a heater core on a 240 is a
> *major* job, having spent the better part of a day on one. Thankfully I
> haven't had to find out on any newer cars yet but it doesn't look real
> easy to get to on my 740 either.

The 740 is no easier than the 240 (haven't done a 240, but I'll take your
word!). The first time it took me three days because the Haynes manual
indicated the dash didn't have to come out. Technically, I suppose it
doesn't, but it's really *much* easier to remove the dash. There is no hard
part that way (just a whole lot of tedious parts), but the passenger
compartment looks like an explosion in a wire factory by the time you get
that far.

Glad to hear about the 850.

Mike