2008 Coolant conditioner

[M.J.]

what will the oil cooler and bigger pan do to prevent a head gasket
failure ?

Improving heat dissipation or lowering engine temperature
should in theory be helpful as exessive heat can over time
weaken a head gasket. It's a combination of pressure and
heat that ruins many head gaskets. Also corrosion from old
acidic coolant, and thermal cycling. Thermal cycling or whatever
its called is when the block is repetitively expanding when hot
and contracting when cool, which over time has the effect of
loosening gasket seal/fit.

I don't know exactly what is/or was the culprit for the
2.5l engine's problems, i.e. whether it is more heat related
or pressure related, or thermal cycling related. You can
fairly easily improve heat dissipation, and hope that this
together with frequent coolant changes (to assure good
ph levels) plus the coolant conditioner is enough to prevent
problems.

Of course, you can counter argue that if it is a heat related
problem, and heat is fairly easy to reduce (somewhat)
then Subaru would have solved the problem a long time
ago by simply increasing oil capacity by a quart or two.
Well, things get complicated if you try to be rational.

I suspect the problem may be more pressure, or thermal
cycling related. Reducing engine operating temperature
should help a tiny bit if the failures are thermal cycling
related. If purely pressure related I don't know if there
is anything an owner can do to help much. Using a very
thin oil could perhaps (?) make a tiny difference, I don't
know.

M.J.

 

[Bugalugs]

Improving heat dissipation or lowering engine temperature
should in theory be helpful as exessive heat can over time
weaken a head gasket. It's a combination of pressure and
heat that ruins many head gaskets. Also corrosion from old
acidic coolant, and thermal cycling. Thermal cycling or whatever
its called is when the block is repetitively expanding when hot
and contracting when cool, which over time has the effect of
loosening gasket seal/fit.

I don't know exactly what is/or was the culprit for the
2.5l engine's problems, i.e. whether it is more heat related
or pressure related, or thermal cycling related. You can
fairly easily improve heat dissipation, and hope that this
together with frequent coolant changes (to assure good
ph levels) plus the coolant conditioner is enough to prevent
problems.

Of course, you can counter argue that if it is a heat related
problem, and heat is fairly easy to reduce (somewhat)
then Subaru would have solved the problem a long time
ago by simply increasing oil capacity by a quart or two.
Well, things get complicated if you try to be rational.

I suspect the problem may be more pressure, or thermal
cycling related. Reducing engine operating temperature
should help a tiny bit if the failures are thermal cycling
related. If purely pressure related I don't know if there
is anything an owner can do to help much. Using a very
thin oil could perhaps (?) make a tiny difference, I don't
know.

M.J.

So to test your theory you would go to all the trouble of installing
extra oil cooling and then the thermostat would notices that the engine
isn't up to correct operation temperature so it would compensate.

Wouldn't it have been easier to install a thermostat with a lower
operating temperature.

 

[M.J.]

So to test your theory you would go to all the trouble of installing extra
oil cooling and then the thermostat would notices that the engine isn't up
to correct operation temperature so it would compensate.

Yes, because I am trying to reduce or dissipate heat that builds-up
after the thermostat opens. At this time the thermostat cannot compensate
in any way.

Wouldn't it have been easier to install a thermostat with a lower
operating temperature.

No, I don't think so. It would just open say 5 or 10 degrees F
earlier but not help dissipate heat above its opening temp.

M.J.

 

[M.J.]

Improving heat dissipation or lowering engine temperature
should in theory be helpful as exessive heat can over time
weaken a head gasket. It's a combination of pressure and
heat that ruins many head gaskets. Also corrosion from old
acidic coolant, and thermal cycling. Thermal cycling or whatever
its called is when the block is repetitively expanding when hot
and contracting when cool, which over time has the effect of
loosening gasket seal/fit.

I don't know exactly what is/or was the culprit for the
2.5l engine's problems, i.e. whether it is more heat related
or pressure related, or thermal cycling related. You can
fairly easily improve heat dissipation, and hope that this
together with frequent coolant changes (to assure good
ph levels) plus the coolant conditioner is enough to prevent
problems.

Of course, you can counter argue that if it is a heat related
problem, and heat is fairly easy to reduce (somewhat)
then Subaru would have solved the problem a long time
ago by simply increasing oil capacity by a quart or two.
Well, things get complicated if you try to be rational.

I suspect the problem may be more pressure, or thermal
cycling related. Reducing engine operating temperature
should help a tiny bit if the failures are thermal cycling
related. If purely pressure related I don't know if there
is anything an owner can do to help much. Using a very
thin oil could perhaps (?) make a tiny difference, I don't
know.

I forgot to add, using an upper cylinder lubricant such as
Marvel Mystery Oil, in the gasoline, may help reduce heat
buildup in the upper cylinders by reducing friction there.
This could potentially also be a bit helpful in avoiding head
gasket problems. MMO is also proven to help avoid burnt
exaust valves.

M.J.



M.J.

 

[Rick Courtright]

what will the oil cooler and bigger pan do to prevent a head gasket
failure ?

Hi,

Short answer: not a d___ed thing.

Long answer: if anything even measurable, it won't be much more than the
original equipment design.

Even longer answer: some people miss the nature of the problem and apply
even stranger band-aids than the factory. I prepared a detailed
explanation of some of the factors involved in head gasket failures
(none of them involved oil, BTW), then deleted it, figuring, "Hey, if
someone thinks an oil cooler or bigger oil pan's gonna save their
headgaskets, more power to 'em." People make good livings off that kind
of thought process. Who am I to interfere?

With that, I think I'll go pop the cap on a longneck w/ Carl and not
worry much about it.

Rick

 

[M.J.]

Hi,

Short answer: not a d___ed thing.

Long answer: if anything even measurable, it won't be much more than the
original equipment design.

Even longer answer: some people miss the nature of the problem and apply
even stranger band-aids than the factory. I prepared a detailed
explanation of some of the factors involved in head gasket failures
(none of them involved oil, BTW), then deleted it, figuring, "Hey, if
someone thinks an oil cooler or bigger oil pan's gonna save their
headgaskets, more power to 'em." People make good livings off that kind
of thought process. Who am I to interfere?

Well, me thinks that in the end you just came to your senses and
deleted whatever you wrote. The main point of the argument is not
oil per se but improved engine heat dissipation that extra amounts of
oil ,or an cooler, facilitates. The temperature reduction argument, as
an argument is fairly strong, so why pick a fight you cannot win, right?

Let me say this, I never claimed that an engine oil cooler, or bigger pan,
is the solution. My opinion is that together with the coolant conditioner
it is probably worth the money. An extra edge of sorts, quite possibly
the only thing that a proactive owner can easily do, that is also good
for overall engine longevity.

M.J.

 

[M.J.]

Here is an interesting take on high engine oil temps and head gasket
failures:

http://www.mgf.ultimatemg.com/group2/common_problems/HGF_pages/why_do_hgfs.htm
Oil temperature as a potential cause of HGF:

It has been suggested that HGF maybe more likely in cars running with high
oil temperatures.

Why?

Because of the following reasons:

1.. HGF is caused, at least in part, by the movement of the cylinder head
over the block, which causes the head gasket's rubber beeding to fail
through shear stress, and thus lead to escape of coolant.
2.. This movement is caused by engine block twisting under high torque
loads, and also - the import bit for this discussion - due to differential
expansion due to different temperatures in the head and the block.
3.. The cylinder head is primarily cooled by water. The block is primarily
cooled by oil.
4.. Under high loads, the engine temperature increases (more work, more
heat). This heat is disappated by the oil and water circulation. Oil is
cooled by heat radiation into the airflow under the car (marginal in a
mid-engined vehicle) whilst water is cooled by the radiator; water cooling
here is much more efficient due to that large air/water heat exchanger known
as the radiator.
5.. If the engine is working hard, the oil temperature will continue to
rise, whilst, due to the opening of the thermostat, the water temperature is
reduced.
6.. Water temperature is lower than the oil temperature. This means that
the cylinder head is cooler than the cylinder block: the block and the head
will expand at different rates = shear stress on head gasket.
7.. Temperature gradient problem is exacerbated when the thermostat opens
and allows cold water (that has been sitting, being cooled by the airflow
through the radiator) to enter the cylinder head. Suddenly, the head is even
colder than the cylinder block... head contracts, whilst block expands =
significant shear stress on head gasket.
So, given this premise, if your engine's oil temperature is regularly above
120ºC, the problem with differential head/block expansion is going to be
significantly worse than when the oil temperature remains in the 90-100ºC
range (closer to the 'regulated' water temperature).

Based on these premises, a water/oil heat exchanger may be beneficial in
matching cylinder head and block temperatures, and limit the heat expansion
mediated shear stress on the head gasket.

http://www.mgf.ultimatemg.com/group2/common_problems/HGF_pages/why_do_hgfs.htm

 

[Bugalugs]

Well, me thinks that in the end you just came to your senses and
deleted whatever you wrote. The main point of the argument is not
oil per se but improved engine heat dissipation that extra amounts of
oil ,or an cooler, facilitates. The temperature reduction argument, as
an argument is fairly strong, so why pick a fight you cannot win, right?

Let me say this, I never claimed that an engine oil cooler, or bigger pan,
is the solution. My opinion is that together with the coolant conditioner
it is probably worth the money. An extra edge of sorts, quite possibly
the only thing that a proactive owner can easily do, that is also good
for overall engine longevity.

M.J.

Why not just buy the 2L, 2L turbo or the 3L.

It is my understanding that the problem was when the 2L block was opened
out to 2.5L.

This left less space between the cylinders and the oil/coolant
passageways where they passed through the head to the block.

The original and the first redesigned gasket was not adequate.

No amount of extra oil cooling is going to solve that.

The second redesign and the current designs have solved the problem.

'course I could be completely wrong

Pass one over here too will ya

 

[M.J.]

Why not just buy the 2L, 2L turbo or the 3L.

There isn't much choice here in the States, where Subaru
sells only two engines, the 2.5L and the six cylinder.

M.J.

 

[Rick Courtright]

Pass one over here too will ya

Got one iced up w/ your name on it, Bug!

Rick