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Volvo 850 1996 - Mystery of the Diasppearing Coolant

 
Chris
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Posts: n/a
 
      20-04-2007
850 with 20v 2.5l engine. 115,000km from new with full main dealer
service history, Recently the collant light went on. Checked coolant,
needed a litre of so to bring back to max line. After 150km city
driving, needed another litre. Then went on 750km country trip. No
coolant loss whatsoever. Think to myself, that was weird, but must be
ok now.

Now, another 200km later of city driving coolant light back on and it
took 2 litres to bring back to max line.

Is it leaking heater core? - don't think so as no wet carpets or other
evidence of leak in cabin. No funny smell when heater turned on.

Is it head gasket? - don't think so as engine runs smooth, no
overheating at all when running (even when coolant was low guage bang
slap in middle), and no white vapour from tailpipe).

Coolant is clean, oil is clean.

No evidence of any leaks under the bonnet.

Radiator hoses are not pressurised (easy to squeeze together when
engine running).

Where is the coolant going?????

 
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James Sweet
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Posts: n/a
 
      20-04-2007
Chris wrote:
> 850 with 20v 2.5l engine. 115,000km from new with full main dealer
> service history, Recently the collant light went on. Checked coolant,
> needed a litre of so to bring back to max line. After 150km city
> driving, needed another litre. Then went on 750km country trip. No
> coolant loss whatsoever. Think to myself, that was weird, but must be
> ok now.
>
> Now, another 200km later of city driving coolant light back on and it
> took 2 litres to bring back to max line.
>
> Is it leaking heater core? - don't think so as no wet carpets or other
> evidence of leak in cabin. No funny smell when heater turned on.
>
> Is it head gasket? - don't think so as engine runs smooth, no
> overheating at all when running (even when coolant was low guage bang
> slap in middle), and no white vapour from tailpipe).
>
> Coolant is clean, oil is clean.
>
> No evidence of any leaks under the bonnet.
>
> Radiator hoses are not pressurised (easy to squeeze together when
> engine running).
>
> Where is the coolant going?????
>



I had a problem like this with my 740 years ago, ended up being a hose
clamp with a slightly stripped adjustment screw, it was tight enough to
not leak until the cooling system heated up and pressurized, but by that
point it was hot enough and the leak small enough that it came out as
invisible steam. I found it by pressurizing the cold cooling system with
a sports ball hand pump, a few PSI is enough, it started pissing out
around the clamp. I used the hose to the expansion tank but I've heard
of installing a tire valve stem in a spare radiator cap. It's a trick
worth trying before you do more drastic things, but if it doesn't
visibly leak you should turn the engine over by hand to make sure it
isn't hydrolocked from coolant leaking into a cylinder before you try
starting it.
 
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blurp
Guest
Posts: n/a
 
      20-04-2007
On Fri, 20 Apr 2007 08:05:08 GMT, James Sweet <(E-Mail Removed)>
wrote:

>Chris wrote:
>> 850 with 20v 2.5l engine. 115,000km from new with full main dealer
>> service history, Recently the collant light went on. Checked coolant,
>> needed a litre of so to bring back to max line. After 150km city
>> driving, needed another litre. Then went on 750km country trip. No
>> coolant loss whatsoever. Think to myself, that was weird, but must be
>> ok now.
>>
>> Now, another 200km later of city driving coolant light back on and it
>> took 2 litres to bring back to max line.
>>
>> Is it leaking heater core? - don't think so as no wet carpets or other
>> evidence of leak in cabin. No funny smell when heater turned on.
>>
>> Is it head gasket? - don't think so as engine runs smooth, no
>> overheating at all when running (even when coolant was low guage bang
>> slap in middle), and no white vapour from tailpipe).
>>
>> Coolant is clean, oil is clean.
>>
>> No evidence of any leaks under the bonnet.
>>
>> Radiator hoses are not pressurised (easy to squeeze together when
>> engine running).
>>
>> Where is the coolant going?????
>>

>
>
>I had a problem like this with my 740 years ago, ended up being a hose
>clamp with a slightly stripped adjustment screw, it was tight enough to
>not leak until the cooling system heated up and pressurized, but by that
>point it was hot enough and the leak small enough that it came out as
>invisible steam. I found it by pressurizing the cold cooling system with
>a sports ball hand pump, a few PSI is enough, it started pissing out
>around the clamp. I used the hose to the expansion tank but I've heard
>of installing a tire valve stem in a spare radiator cap. It's a trick
>worth trying before you do more drastic things, but if it doesn't
>visibly leak you should turn the engine over by hand to make sure it
>isn't hydrolocked from coolant leaking into a cylinder before you try
>starting it.


Another point of leakage (for similar reasons as described above) is
the water pump gasket. Mine only seemed to leak once the car was shut
off and the engine temperature went up because the coolant has stopped
flowing, further pressurizing the system.

blurp


 
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Chris
Guest
Posts: n/a
 
      20-04-2007
On Apr 21, 12:25 am, blurp <(E-Mail Removed)> wrote:
> On Fri, 20 Apr 2007 08:05:08 GMT, James Sweet <(E-Mail Removed)>
> wrote:
>
>
>
>
>
> >Chris wrote:
> >> 850 with 20v 2.5l engine. 115,000km from new with full main dealer
> >> service history, Recently the collant light went on. Checked coolant,
> >> needed a litre of so to bring back to max line. After 150km city
> >> driving, needed another litre. Then went on 750km country trip. No
> >> coolant loss whatsoever. Think to myself, that was weird, but must be
> >> ok now.

>
> >> Now, another 200km later of city driving coolant light back on and it
> >> took 2 litres to bring back to max line.

>
> >> Is it leaking heater core? - don't think so as no wet carpets or other
> >> evidence of leak in cabin. No funny smell when heater turned on.

>
> >> Is it head gasket? - don't think so as engine runs smooth, no
> >> overheating at all when running (even when coolant was low guage bang
> >> slap in middle), and no white vapour from tailpipe).

>
> >> Coolant is clean, oil is clean.

>
> >> No evidence of any leaks under the bonnet.

>
> >> Radiator hoses are not pressurised (easy to squeeze together when
> >> engine running).

>
> >> Where is the coolant going?????

>
> >I had a problem like this with my 740 years ago, ended up being a hose
> >clamp with a slightly stripped adjustment screw, it was tight enough to
> >not leak until the cooling system heated up and pressurized, but by that
> >point it was hot enough and the leak small enough that it came out as
> >invisible steam. I found it by pressurizing the cold cooling system with
> >a sports ball hand pump, a few PSI is enough, it started pissing out
> >around the clamp. I used the hose to the expansion tank but I've heard
> >of installing a tire valve stem in a spare radiator cap. It's a trick
> >worth trying before you do more drastic things, but if it doesn't
> >visibly leak you should turn the engine over by hand to make sure it
> >isn't hydrolocked from coolant leaking into a cylinder before you try
> >starting it.

>
> Another point of leakage (for similar reasons as described above) is
> the water pump gasket. Mine only seemed to leak once the car was shut
> off and the engine temperature went up because the coolant has stopped
> flowing, further pressurizing the system.
>
> blurp- Hide quoted text -
>
> - Show quoted text -


That is an interesting point, but would I not expect to see leakage on
the engine or on the ground? There is no evidence of leaks at all
(that I can see)

Chris

 
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Baz
Guest
Posts: n/a
 
      20-04-2007


"Chris" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) ups.com...
> On Apr 21, 12:25 am, blurp <(E-Mail Removed)> wrote:
> > On Fri, 20 Apr 2007 08:05:08 GMT, James Sweet <(E-Mail Removed)>
> > wrote:
> >
> >
> >
> >
> >
> > >Chris wrote:
> > >> 850 with 20v 2.5l engine. 115,000km from new with full main dealer
> > >> service history, Recently the collant light went on. Checked coolant,
> > >> needed a litre of so to bring back to max line. After 150km city
> > >> driving, needed another litre. Then went on 750km country trip. No
> > >> coolant loss whatsoever. Think to myself, that was weird, but must be
> > >> ok now.

> >
> > >> Now, another 200km later of city driving coolant light back on and it
> > >> took 2 litres to bring back to max line.

> >
> > >> Is it leaking heater core? - don't think so as no wet carpets or

other
> > >> evidence of leak in cabin. No funny smell when heater turned on.

> >
> > >> Is it head gasket? - don't think so as engine runs smooth, no
> > >> overheating at all when running (even when coolant was low guage bang
> > >> slap in middle), and no white vapour from tailpipe).

> >
> > >> Coolant is clean, oil is clean.

> >
> > >> No evidence of any leaks under the bonnet.

> >
> > >> Radiator hoses are not pressurised (easy to squeeze together when
> > >> engine running).

> >
> > >> Where is the coolant going?????

> >
> > >I had a problem like this with my 740 years ago, ended up being a hose
> > >clamp with a slightly stripped adjustment screw, it was tight enough to
> > >not leak until the cooling system heated up and pressurized, but by

that
> > >point it was hot enough and the leak small enough that it came out as
> > >invisible steam. I found it by pressurizing the cold cooling system

with
> > >a sports ball hand pump, a few PSI is enough, it started pissing out
> > >around the clamp. I used the hose to the expansion tank but I've heard
> > >of installing a tire valve stem in a spare radiator cap. It's a trick
> > >worth trying before you do more drastic things, but if it doesn't
> > >visibly leak you should turn the engine over by hand to make sure it
> > >isn't hydrolocked from coolant leaking into a cylinder before you try
> > >starting it.

> >
> > Another point of leakage (for similar reasons as described above) is
> > the water pump gasket. Mine only seemed to leak once the car was shut
> > off and the engine temperature went up because the coolant has stopped
> > flowing, further pressurizing the system.
> >
> > blurp- Hide quoted text -
> >
> > - Show quoted text -

>
> That is an interesting point, but would I not expect to see leakage on
> the engine or on the ground? There is no evidence of leaks at all
> (that I can see)
>
> Chris
>


If as you suspect the water is going into the engine and being "burnt" with
the fuel, it is probably not in all cylinders. You should be able to see a
difference in the condition of the spark plugs, the one with water entering
should look cleaner than those without. If you can somehow get a view down
the plug holes the piston top should also be cleaner.

By the way I used to run water injection on another car, it pinged on 91
octane unleaded - that cured it, and your water consumption is around the
amounts I used, although it was going into all 4 cylinders. I had no
evidence of white vapour from the tailpipe, although it's often very hard to
see your own tailpipe while you're driving. So if it is going into the
engine, you will probably see no ill effects in running from this amount.
Maybe even an improvement.

My 1996 850, upon refilling with coolant will often undergo a major drop in
level overnight, some inches in the expansion tank, and it has emptied the
tank on one occasion less than an hour after refilling. After a couple of
days of this it stabilises and is then ok for a long time, until once again
disturbed. I suspect air locks in the system, that bleed themselves out.
I've gotten used to this and now expect it.

You mentioned that your radiator hoses were not pressurised. Perhaps the
expansion tank cap is not sealing. Buy another one. I had one on an
earlier 740 Volvo (cap looks the same by the way) and although it looked ok
and the valves and gasket seemed ok, a new one cured the leak on that car.
But there were stains around the cap indicating a leak.

Coolant leaks often do not reach the ground, but will always leave a residue
on something showing its path on the way out. If enough leaks out, you can
generally locate it with careful examination. That is if you are using the
proper coolant and not just water (If you're losing enough $$$, perhaps
you're down to just adding water?)

Lastly I had heard that some 850s had problems with porous cylinder heads.
It was aggravated by not using proper coolant. Perhaps someone else can add
some information here.

Regards
Barry





 
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Chris
Guest
Posts: n/a
 
      22-04-2007
On Apr 21, 8:05 am, "Baz" <(E-Mail Removed)> wrote:
> "Chris" <(E-Mail Removed)> wrote in message
>
> news:(E-Mail Removed) ups.com...
>
>
>
>
>
> > On Apr 21, 12:25 am, blurp <(E-Mail Removed)> wrote:
> > > On Fri, 20 Apr 2007 08:05:08 GMT, James Sweet <(E-Mail Removed)>
> > > wrote:

>
> > > >Chris wrote:
> > > >> 850 with 20v 2.5l engine. 115,000km from new with full main dealer
> > > >> service history, Recently the collant light went on. Checked coolant,
> > > >> needed a litre of so to bring back to max line. After 150km city
> > > >> driving, needed another litre. Then went on 750km country trip. No
> > > >> coolant loss whatsoever. Think to myself, that was weird, but must be
> > > >> ok now.

>
> > > >> Now, another 200km later of city driving coolant light back on and it
> > > >> took 2 litres to bring back to max line.

>
> > > >> Is it leaking heater core? - don't think so as no wet carpets or

> other
> > > >> evidence of leak in cabin. No funny smell when heater turned on.

>
> > > >> Is it head gasket? - don't think so as engine runs smooth, no
> > > >> overheating at all when running (even when coolant was low guage bang
> > > >> slap in middle), and no white vapour from tailpipe).

>
> > > >> Coolant is clean, oil is clean.

>
> > > >> No evidence of any leaks under the bonnet.

>
> > > >> Radiator hoses are not pressurised (easy to squeeze together when
> > > >> engine running).

>
> > > >> Where is the coolant going?????

>
> > > >I had a problem like this with my 740 years ago, ended up being a hose
> > > >clamp with a slightly stripped adjustment screw, it was tight enough to
> > > >not leak until the cooling system heated up and pressurized, but by

> that
> > > >point it was hot enough and the leak small enough that it came out as
> > > >invisible steam. I found it by pressurizing the cold cooling system

> with
> > > >a sports ball hand pump, a few PSI is enough, it started pissing out
> > > >around the clamp. I used the hose to the expansion tank but I've heard
> > > >of installing a tire valve stem in a spare radiator cap. It's a trick
> > > >worth trying before you do more drastic things, but if it doesn't
> > > >visibly leak you should turn the engine over by hand to make sure it
> > > >isn't hydrolocked from coolant leaking into a cylinder before you try
> > > >starting it.

>
> > > Another point of leakage (for similar reasons as described above) is
> > > the water pump gasket. Mine only seemed to leak once the car was shut
> > > off and the engine temperature went up because the coolant has stopped
> > > flowing, further pressurizing the system.

>
> > > blurp- Hide quoted text -

>
> > > - Show quoted text -

>
> > That is an interesting point, but would I not expect to see leakage on
> > the engine or on the ground? There is no evidence of leaks at all
> > (that I can see)

>
> > Chris

>
> If as you suspect the water is going into the engine and being "burnt" with
> the fuel, it is probably not in all cylinders. You should be able to see a
> difference in the condition of the spark plugs, the one with water entering
> should look cleaner than those without. If you can somehow get a view down
> the plug holes the piston top should also be cleaner.
>
> By the way I used to run water injection on another car, it pinged on 91
> octane unleaded - that cured it, and your water consumption is around the
> amounts I used, although it was going into all 4 cylinders. I had no
> evidence of white vapour from the tailpipe, although it's often very hard to
> see your own tailpipe while you're driving. So if it is going into the
> engine, you will probably see no ill effects in running from this amount.
> Maybe even an improvement.
>
> My 1996 850, upon refilling with coolant will often undergo a major drop in
> level overnight, some inches in the expansion tank, and it has emptied the
> tank on one occasion less than an hour after refilling. After a couple of
> days of this it stabilises and is then ok for a long time, until once again
> disturbed. I suspect air locks in the system, that bleed themselves out.
> I've gotten used to this and now expect it.
>
> You mentioned that your radiator hoses were not pressurised. Perhaps the
> expansion tank cap is not sealing. Buy another one. I had one on an
> earlier 740 Volvo (cap looks the same by the way) and although it looked ok
> and the valves and gasket seemed ok, a new one cured the leak on that car.
> But there were stains around the cap indicating a leak.
>
> Coolant leaks often do not reach the ground, but will always leave a residue
> on something showing its path on the way out. If enough leaks out, you can
> generally locate it with careful examination. That is if you are using the
> proper coolant and not just water (If you're losing enough $$$, perhaps
> you're down to just adding water?)
>
> Lastly I had heard that some 850s had problems with porous cylinder heads.
> It was aggravated by not using proper coolant. Perhaps someone else can add
> some information here.
>
> Regards
> Barry- Hide quoted text -
>
> - Show quoted text -


I looked at the filler cap - no evidence of any leakage whatsoever.
The date of manufacture is 2003, so I presume the original failed and
was then replaced.I have cheked all the water connections. Some have a
white powdery type of residue (such as the heater pipes on the
firewall) but nothing tha appears to be a current leak.

I don't actually suspect the water is entering the combustion chambers
- I believe it must be a leak of some sort.

I have just come back from a 200 mile drive and the car used no
coolant whatsoever. Ehat really do not understand is why it consumes
water in city driving, but not on the highway. On a long drive the
engine gets a good rev, I a not scared of redline. My wife thnks the
coolant los correlates with her use of he airconditioning, but surely
the systm are completel independent?????

 
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Michael Pardee
Guest
Posts: n/a
 
      22-04-2007
"Chris" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) ps.com...
>
> I have just come back from a 200 mile drive and the car used no
> coolant whatsoever. Ehat really do not understand is why it consumes
> water in city driving, but not on the highway. On a long drive the
> engine gets a good rev, I a not scared of redline. My wife thnks the
> coolant los correlates with her use of he airconditioning, but surely
> the systm are completel independent?????
>
>

Two clues in that:
*long drives keep the cooling system pressurized, while a succession of
trips (maybe typical of city driving?) causes the coolant to be pushed into
the reservoir when the engine heats up and slurped back up when the engine
cools. If the recovery hose is split, like at the radiator neck, the coolant
can be lost in the transfer. I've also had grief from the seal at the
radiator cap leaking, causing the system to pump coolant into the reservoir
when heating and sucking air back in when cooling. That causes the reservoir
to get overfilled, though. Regardless, if the radiator cap is more than a
couple years old this is a good time to replace it with a new Volvo cap -
aftermarket radiator caps and thermostats are unreliable.
*The A/C affects part of the cooling system: the radiator. Since the A/C
condensor is in front of the radiator, using the A/C raises the radiator
temperature and in that way raises the temperature of most of the coolant in
the system. That means more expansion and more cycling into and out of the
reservoir (previous paragraph).

Mike



 
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Chris
Guest
Posts: n/a
 
      22-04-2007
On Apr 22, 10:49 pm, "Michael Pardee" <(E-Mail Removed)>
wrote:
> "Chris" <(E-Mail Removed)> wrote in message
>
> news:(E-Mail Removed) ps.com...
>
> > I have just come back from a 200 mile drive and the car used no
> > coolant whatsoever. Ehat really do not understand is why it consumes
> > water in city driving, but not on the highway. On a long drive the
> > engine gets a good rev, I a not scared of redline. My wife thnks the
> > coolant los correlates with her use of he airconditioning, but surely
> > the systm are completel independent?????

>
> Two clues in that:
> *long drives keep the cooling system pressurized, while a succession of
> trips (maybe typical of city driving?) causes the coolant to be pushed into
> the reservoir when the engine heats up and slurped back up when the engine
> cools. If the recovery hose is split, like at the radiator neck, the coolant
> can be lost in the transfer. I've also had grief from the seal at the
> radiator cap leaking, causing the system to pump coolant into the reservoir
> when heating and sucking air back in when cooling. That causes the reservoir
> to get overfilled, though. Regardless, if the radiator cap is more than a
> couple years old this is a good time to replace it with a new Volvo cap -
> aftermarket radiator caps and thermostats are unreliable.
> *The A/C affects part of the cooling system: the radiator. Since the A/C
> condensor is in front of the radiator, using the A/C raises the radiator
> temperature and in that way raises the temperature of most of the coolant in
> the system. That means more expansion and more cycling into and out of the
> reservoir (previous paragraph).
>
> Mike


Good suggestions - I will purchase a new radiator cap at Volvo dealer
today - can't be that many $$$ (I hope!) and will at least discount
one potential issue. However, if there was loss between engine and
expnsion tank I would have thought it would be visible - I can't see
any loss.

Chris

 
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moster
Guest
Posts: n/a
 
      23-04-2007
Chris, I hate to be the bearer of bad news, but...it could very well be your
head gasket. You may NOT see anything at all on the outside as far as
evedence is concerned because it may be getting compressed and burned. Start
your car and remove the coolant cap. Watch for about thirty minutes or until
you see coolant come bubbling out of reservoir. If the the temperature is ok
and coolant comes out of reservoir what is happening is your head gasket is
blowing compression into the cooling system. When that happens, and chances
are that it will happen at higher speeds, your cooling system cannot handle
that much pressure and releases coolant as you are driving down the road.
Happened to my Chrysler LHS and it, like yours, had no symptoms anything was
wrong.

"Chris" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed) oups.com...
> 850 with 20v 2.5l engine. 115,000km from new with full main dealer
> service history, Recently the collant light went on. Checked coolant,
> needed a litre of so to bring back to max line. After 150km city
> driving, needed another litre. Then went on 750km country trip. No
> coolant loss whatsoever. Think to myself, that was weird, but must be
> ok now.
>
> Now, another 200km later of city driving coolant light back on and it
> took 2 litres to bring back to max line.
>
> Is it leaking heater core? - don't think so as no wet carpets or other
> evidence of leak in cabin. No funny smell when heater turned on.
>
> Is it head gasket? - don't think so as engine runs smooth, no
> overheating at all when running (even when coolant was low guage bang
> slap in middle), and no white vapour from tailpipe).
>
> Coolant is clean, oil is clean.
>
> No evidence of any leaks under the bonnet.
>
> Radiator hoses are not pressurised (easy to squeeze together when
> engine running).
>
> Where is the coolant going?????
>


 
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Michael Pardee
Guest
Posts: n/a
 
      23-04-2007
"moster" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> Chris, I hate to be the bearer of bad news, but...it could very well be
> your head gasket. You may NOT see anything at all on the outside as far as
> evedence is concerned because it may be getting compressed and burned.
> Start your car and remove the coolant cap. Watch for about thirty minutes
> or until you see coolant come bubbling out of reservoir. If the the
> temperature is ok and coolant comes out of reservoir what is happening is
> your head gasket is blowing compression into the cooling system. When that
> happens, and chances are that it will happen at higher speeds, your
> cooling system cannot handle that much pressure and releases coolant as
> you are driving down the road. Happened to my Chrysler LHS and it, like
> yours, had no symptoms anything was wrong.
>


What makes me think elsewhere is that the coolant holds up well in highway
driving. That is usually worst case for head gasket coolant consumption.

Mike



 
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