I have a 2001 S10. For a few years now, it has been losing coolant. I
just added a full gallon to the overflow container. I have done that
before, maybe three times now.
I see no evidence of leakage under the truck. Performance seems just
fine. I am wondering....could I have head gasket leakage? Should I
fix it? The truck has 90K miles on it, and has had zero repairs. Uses
Since this a home repair newsgroup, you should remember to start the
subject line of non-home-repair related posts with OT so that members will
know that your post is "off topic". At first I thought this might be a
central air conditioning question.
That said, an automobile's coolant system will sometimes only leak when it
is under pressure. The pressure goes up as the engine gets hotter. The leak
then hits the hot engine and evaporates before you ever see it. By the time
the engine cools enough to no longer boil off the leaked fluid, the leak
stops because the pressure goes down. The result is that you won't see any
fluid under the truck.
An auto repair shop can pressurize the system while it is cool and
sometimes reveal the leak. It often doesn't take much pressure to find a
leak in a cracked hose or loose clamp.
On 7/6/14, 6:19 PM, snipped-for-privacy@Taiwan.com wrote:
Subaru had some problems with head gaskets a few years ago. One of
the fixes was just to add some radiator sealant. It was a specific
Subaru part. I bought some on Ebay.
I don't know if it was something super special or just regular
coolant system sealant with the Subaru logo.
It certainly COULD be a leaking cylinder head gasket. A small leak will
not reduce engine performance sufficiently to be noticable.
I had a 1992 Chevrolet Cavalier that was losing coolant due to a leaking
cylinder head gasket, and I only had it repaired once the leakage was
bad enough that it was affecting the car's starting and idling.
Nowadays most cars have aluminum cylinder heads to save weight, but
these are notorious for warping after 100 thousand miles or so and the
cylinder head has to be removed, rebuilt and replaced.
But, it would check the simple and cheap stuff first. I would replace
the radiator cap. After repeated heating and cooling, the spring
tension in the radiator cap can get weak so that your coolant may very
well be escaping in the form of steam and ethylene glycol vapours from a
radiator cap that's got a weak spring in it. If replacing the radiator
cap doesn't resolve the problem, then I'd have the cooling system
pressure tested to see if it's holding pressure or not. And, if it's
not holding pressure, and the coolant isn't leaking OUT of the engine,
then it's leaking IN TO the engine.
Check your oil dipstick. If antifreeze is leaking into the crank case,
it'll muck up the oil. If the oil on your dip stick looks normal, then
at least you can be confident it's not leaking into the crank case.
It is my understanding that coolant system sealants can be trouble. Since
it's the job of the particles and the other sealant compounds to find small
passageways that might be leaks, they can block the actual water channels
in older radiators with already partially clogged arteries. They can clog
heater cores too.
I've always heard that at best they will buy you some time, but eventually
you will need to replace whatever was leaking, assuming that they don't
cause more problems in the meantime.
First thing is to check all hose connections for white or pink
powdery residue.. Replace all spring type hose clamps with screw type
clamps. If that doesn't solve it, add a cooling system sealer. A
simple stop-leak cube is usually more than sufficient, ot Knight's
Aluma-seal powder - but follow the directions to the letter. This
will handle external seepage even in a head gasket. If there is no
white foam in the rocker cover, the coolant is not getting into the
My guess is it is getting out as a vapour at one or more hose
On Mon, 7 Jul 2014 02:09:43 +0000 (UTC), DerbyDad03
Properly applied they can litterally be lifesavers. And The heater
core on my '57 Fargo went over 20 years without a leak after adding 1
stop leak cube. The important thing is to FOLLOW DIRECTIONS. Second
important thing is to use the right product. I've never had problems
with stop-leak cube or knights alumaseal. (same stuff as silver-seal)
I am not a fan of BarsLeaks, The prestone stuff isn't bad.
That's the beauty of the InterWeb.
In this thread...
...a mechanic said:
"...there is one brand I have used for decades without any clogging issues
that I know of, and that is Bar's Leaks. They have several products; I am
referring to the original Bar's Leaks Radiator Stop Leak. It has been used
as a factory-applied product by some vehicle manufacturers. I have no
qualms about using it in my cars or in my customers' cars."
On Sunday, July 6, 2014 11:09:12 PM UTC-4, DerbyDad03 wrote:
barrs leak clogged my heater core requiring it be replaced. It was a very expensive disassemble the dash to replace the heater core.
The leak was eventually traced to a water pump that only leaked now and then.....
If there is no visible leak, coolant can evaporate, or burn.
1. Is rad cap good?
2. Have you cooling system presssure tested?
3. Did you put in dye to detect gasket leak?
4. Is there sweet smell from exhaust?
5. rad hoses, clamps in good order?
6. When is the last time you flushed the cooling system?
7. Is the coolant temp. higher than normal range?
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