96 850 GLT - Steam/Vapor coming from Vents

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.

 

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?

 

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

 

Thanks for your reply. Good analysis.

 

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.

 

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

 

I just replaced the core on my 850 - an hour and a half and the new
core was in place.

 

Well, fellow listers, here's the scoop:

I also made a stop at a Volvo, sort of "boutique" repair shop and asked
similar questions. Well, lots of drama here. "Oh, bubbles coming from
the reservoir - well, that's a sure sign of a blown head gasket".

Really now. Could it possibly be a stuck thermostat?

"Oh no, we see this kind of thing all the time in an 850. Yes, we just
did one with a similar problem".

Uh huh. And what was the cost?

"I can look that up, yes, here it is... about $1300.00, let's see $340
for the heater core...."

Ok, thanks for the insight, I'll think about this.

"Shall we send a tow truck?"

No, I need to consider what to do with the car.

So, I check on E-Bay and get a core for $109.00. I call another guy,
who's done work for me and my wife and explain the problem.

It turned out to be the heater core, as part of the problem. Second part
is a stuck thermostat. Replaced both. Car runs perfectly.

Total cost: $109 for heater core, $200 for labor and another $20.00 for
the thermostat, including labor = $329

My thanks to you all for your advice and guidance.