-----Original Message-----
Jim Alexander wrote:

Hours are apparently not the only factor here.  It also is dependent upon
keeping the Zinc's replaced as necessary.

Inspection of the bad transmission cooler revealed that the pencil zinc was
entirely gone, for how long it had been gone we had no idea

REPLY

Please keep in mind that any corrosion is accelerated  when water velocity
increases.
Ditto for temperature,
Therefore hot,  fast flowing  seawater is going to cause rapid  corrosion
compared to the same fitting in still cool water.

The Galvanic table is reference to room temp and  water flow at 4 knots
velocity.

Regards

Arild

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Bob Lowe, Marin, and all,

Thanks for your comments regarding returning used oil to the fuel tanks with
the oil xchanger system.  I tend to agree with you all (and my gut) about
not sending used oil to clean fuel.
About 2 1/2 years ago I installed oil bypass filters on my Cats.  I sent in
oil samples rather than changing the oil and waited till they told me I
should change the oil.  That was this season.  Nothing major.  Just that
they saw particulates building and wanted to see a fresh sample.
I will say that after adding the bypass system, when I check the oil via
dipstick, the oil is brown, even now.  Not jet black, although it is darker
brown than when I first had them installed.  I have about 350 hours on the
engines since the installation.
I'm a believer in the system.  My oil changes were hundreds of dollars and
I've managed to skip a couple, thereby saving more than enough to pay for
the bypass system.
Just my experience.  I'll get something installed so that changing the oil
is a little less painful.

Val Trent
MV Float Plane
1993 50' Vista

Subject: TWL: Providing clean oil (was Solera...)

Changing oil is a real PITA, no question!  I hate to change oil!!!  I dread
it!!!  My knees and back do not like it!!!

I have researched this problem for some time now and have come to the
conclusion that providing oil bypass filtering of sub-micron particles
combined with oil analysis is by far the best way to provide clean oil for
my engines as well as reduce or even eliminate oil changes.  Filters will
still have to be changed, but perhaps not as frequently.  Oil will only have
to be changed when and if oil analysis says it is required.  Oil bypass
filtration is a solution that makes sense to me because it achieves
providing clean oil to the engine, cleaner than it will get otherwise and
eliminates most or all of the negative aspects of changing oil as outlined
above, including the humble body positions and resulting protests.

I have chosen to install Gulf Coast Oil Bypass Filters on both of my John
Deere main engines as well as on my Northern Lights genset.  I will combine
this with regular oil sample analysis to monitor engine wear and oil
quality.  This is by far the best solution to the problem, IMHO.  I chose
Gulf Coast filters because they are effective and can use either a standard
roll of toilet paper or paper towels, depending on size of filter, or a Gulf
Coast filter cartridge.  This is a nice feature, especially if you don't
have a filter cartridge handy.

I welcome comments and other perspectives/opinions.

Good luck,

Bob Lowe

scant quart of oil out of the engine by opening the valve slightly and
directing the flow into an empty 1 quart plastic oil bottle. I then add a
new quart of oil to the engine. The capacity of the engine's small sump is 5
quarts so most of the oil is effectively changed every 100 hours.

Hmm.....  I wonder about this.  A friend used to change the oil in his car
every 3000 miles, but he'd ony change the filter every other oil change.  I
guess to save money.  Anyway, he stopped doing this when someone pointed out
that what he was doing on the "in between" oil changes was essentially
pouring a guart of dirty oil into the new oil.

So I wonder if the method you describe actually gives you any real benefit.
You take out one quart of dirty oil, leave in four, which contaminates the
quart of clean oil a fair amount I should think.  Then you keep run the
engine another twenty hours, putting more soot, acids, whatever, into the
oil, then you drain out one quart, add one fresh quart which is promptly
contaminated by the remaing four quarts of dirty oil, run twenty more hours,
and so on.  It seems to me that what you are really doing is maintaining a
permanently dirty oil condition in the engine. Maybe not as dirty as the oil
would be at the end of a 100 hour oil change interval, but pretty dirty
nevertheless since your ratio of clean oil to dirty oil is never greater
than one to four.<<<<<<<<<

As pointed out by Paul, Alex and John oil additive depletion is a concern
and I failed to address it in my original post.

I guess that in my mind, it was not a problem for me; hence, I did not
include my conclusions on the matter.  What I think I have learned from the
experts is that with normal oil usage of perhaps 1 quart each 100 hours of
operation (use your own number, my engines use a bit more than that),
changing the bypass and main oil filters at 200 hour intervals which
requires the addition of 2 1/2 to 3 quarts of new oil for a total amount of
oil added of 4 1/2 to 5 quarts or more each 200 hours, depending on your oil
consumption, representing 20% to 25% m/l of crankcase/filter capacity, is
probably enough to maintain the additive level within satisfactory levels.
The oil sample analysis should also indicate additive depletion if this
occurs and then one can simply change the oil, if and when this occurs.

In talking with the experts in the laboratories, they have indicated that
with bypass filtering, they have seen many examples of trucks that go well
over 1 and 2 million miles without an oil change or engine overhaul.  That
impresses me.  That equals 20,000 to 40,000 hours of driving at 50 mph and I
equate that to at least 4000 hours for a boat, assuming 1,000,000 miles, avg
speed of 50 mph and a duty of 20% that of a boat.  So if I can reduce my oil
changes to once every 4000 hours or even 25% of that and reduce the wear on
the engines at the same time while saving money, I consider that a good way
to go.

Most of us just change the oil at recommended intervals or so and forget
about it.  That's all well and good, however, there are situations when that
isn't quite good enough.  For example, consider a Ford Lehman 120 that uses
perhaps a quart of oil every 25 hours and has leaky injectors that leak
about the same amount.  The owner of such a boat may never know his oil is
being diluted and is happy because he never has to add oil.  But his engine
is not being properly lubricated as a result of the oil dilution.  Unless he
can and does feel it between his fingers, the only way to know is by having
the oil analyzed.  "Making oil" from leaky injectors is not all that
uncommon.  I don't have that problem on my John Deere engines.

Additional thoughts and input always welcome.

Good luck,

Bob Lowe

----- Original Message -----
From: "Paul Goyette" paul@whooppee.com
[snip]

day,

oil

----- Original Message -----

[snip]
OTOH: There is creditable evidence that the use of a cellulose depth
filter like the GCF will, by thouroughly cleaning the oil, drastically
slow the additive depletion process. There are some fairly basic
chemistry reasons for why this is so and I'm pretty sure that I've
posted some material on this in the dim and distant past. If anyone is
interested, try searching on dithiophosphate or di-thiophosphate at
http://abaco.pwr.com/twl/ .

The premise behind GCF's claim that you can eliminate oil changes is
that, since additive depletion is reduced and a filter element change
requires that enough new oil will need to be added back
into the system (GCF O-1) the resulting additive level will always be
high enough for the task at hand. It's a minor semantic point, but I
would feel more comfortable saying that the GCF could allow you to
eliminate oil DRAINING rather than oil CHANGING. [snip]
----- Original Message -----
From: John Boy "Waka Waka Waka" [jsclipper@earthlink.net]
Engine lube oil DOES breakdown. Particularly the plasticizers used in ALL
modern multi viscosity oils and the numerous additives that make up modern
lube oil. So many additives form the basis for modern lube oil's properties
that the base stock oil seems to be just a carrier for them. They all "wear
out" or are depleted over the oil's "service life". [snip]

There are synthetics such as Amsoil for diesels. Just make sure you have a
synthetic that is specifically approved (CI rating) for diesel. Personally,
I don't think they are cost effective unless you are using them with bypass
filtration. One nice thing about synthetics is that they are made of a
single size molecular chain, rather than dino oil, which is a combination of
thousands of chains that break down at different rates with different end
products, like sludge. I understand that when a synthetic oil chain breaks
down, it essentially turns into a gas and leaves the engine. This is why
engines run on synthetic are so clean when you open them up. Now this last
statement was from Popular Science a LONG time ago, when synthetics were
first developed, so if someone knows better (Alex?) jump right in and
correct me!

Keith
__
Huh?
----- Original Message -----
From: "Frank Bales" fbales@ligtel.com

oils? can they be