Correct Anti Freeze

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Oct 6, 2007
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1983 42' Present Sundeck
Happy New Year to all!!

What is the low down on the correct AF for my 135 Lehman's? We use a "works in everything" in our customer machines that we purchase from O'Reilly. Will this be the best choice on my engines?
Our diesel shop recommends and uses the Caterpillar brand anti-freeze formulated specifically for diesels. In our climate a 50:50 mixture is ideal. One reason they recommend the Cat brand (I don't know who actually makes it) is that it contains ingredients that combat corrosion and buildup inside the engine's coolant passages. When we bought our boat it had Sierra "non-toxic" anti-freeze in the FL120s because of the water heater, and the diesel shop recommended we get it out of the engines asap, which we did. Everyone I know in our marina with engines from FL120s to 400+ hp Cats, John Deere's, Cummins, you name it, uses the Cat brand diesel anti-freeze.

The common practice used to be to change the coolant every so many years or hours. This is no longer the recommendation. Instead, our diesel shop recommends that the coolant be tested every year. If it still meets all the specs, then they leave it in. It is only changed out when it no longer meets whatever the specifications are, which apparently can be many years.
Some diesels carry the cylinders in cast sleves , others just hold the cylinders top and bottom.

The ringing sound of old diesels is the cylinder wall ringing like a bell on combustion.

That ringing moves the cylinder enough to cavitate the coolant in contact with it.

This erodes the cylinder , and can eat thru the cylinder wall

The antifreez has a goop (SCA) in it that causes a slime to grow on all the engine surfaces.

On the cylinder wall the cavitation east the goop, not your cylinder.

So antifreez is removed to flush and chemicaly clean the goop from the entire cooling system , at predetermined service intervals.

The slime can be made up during the antifreez service life withtesting and additions.

Most old engines (low power ) have the cylinder walls inserted in castings , so your favorite auto stuff , with distilled water is fine.

A new high power engine , that needs the coolant in contact with the cylinders , must use antifreez with SCA , and have it changed out on sked.

"The antifreez has a goop (SCA) in it that causes a slime to grow on all the engine surfaces."

This "guru" needs to go back to a cave in the hills.

IF your cooling system has "slime" it has a problem that needs correcting before the engine is damaged. Slime is the result of either bacterial contamination or too a high*silicate or phosphate*concentration. Either is not good and can be caused by various means.

There is a wealth of real information concerning cooling system maintenance on the web. If you have concerns or just want to know how the systems work, search for engine coolant contamination, black slime in coolant, antifreeze additive packages, cooling system maintenance, or similar terms. Contact the engine manufacturer to determine what they reccomend because different engines contain differing metals and may require different additives or treatments.

The "guru" is dangerously ignorant and his advice is a threat to your pocketbook and*your engine's health.*

-- Edited by RickB at 10:40, 2009-01-07
Since this is a bucket of opnions .. heres mine.
I agree with Marin on Cat AF
If you have an engine with no aluminum in contact with the coolant, use any quality product.**
If the coolant comes in contact with aluminum, as in an exhaust manifold, use orange as in " extended life " or a universal AF that is formulated for aluminum. Orange or EL AF did have gelling problems but probably isn't on the market now. Look for " mixes whith all types ". There was a maintanance bullitin from Yanmar recomending extended life AF.
MACS 13 ( a NAPA product ) water pump lubricant is good but be very careful you don't get too much in the system as it will cause an oily mess.

Eric Henning
Is it a 3208??

Ken- great info. As I understand, a thin oxide film forms on the exterior of the liner- or outside the cylinder wall in the case *of a parent bore engine like the 3208 when using the addative package. The swelling of the cylinder- at the time it fires- and the following return to the original size, leaves a void momentarily. Am I missing anything here?
Yep, that's about it. They replaced half a bazillion liners under warranty when they first put out the 3208. IIRC the factory fill AF wasn't adequate and this was one of the first removable liner engines of this particular design for them. It was a great lightweight diesel engine once they fixed the problem.

Back to the original question, I use regular Prestore orange extended life coolant in my Lehman 135. Be sure to only used distilled water to dilute it to specs. Bob Smith from American Diesel said this was just fine, and no special antifreeze was needed for that engine.
Cats 3208 doesn't have a liner in it. It is a parent bore engine. You can maybe bore it one time to rebuild it but then it's a throw away.
I stand corrected. I'm misremembering somehow. I wonder if they were dry sleeves that they were putting in. I don't recall that they were replacing blocks.
I know that when you got a cyclinder in a gas motor that's so messed up you can bore it out and sleeve it and save the block but I don't think you can do that with a diesel due to the pressures invovled in the engine.
Thanks to Keith and all. I just got off the phone with a buddy who is the Cat P Manager in BR. He says their dealership does not sleeve 3208's, but they do send it to a local shop to have it done. Interestingly- Cat does offer a steel sleeve for a 3116 (also born as a parent bore engine).Steve
marin...i`ve been using cat lifetime antifreeze for abt 4 yrs...was talking to a mech/friend in nanaimo, and the lifetime antifreeze came up...he informed me that it`s been found it`s not lifetime any when i got the chance, i called cat in the southcenter local, and discussed it with them...was told that it should be changed every 4 yrs!...mine is gone...i also use the belden coolant additive as per instructions...c
I don't know anything about the Cat "lifetime" product.* The Cat DEAC coolant we use doesn't make that claim on the container.* Our diesel shop recommends the coolant in the engine be checked every year.* If it meets the required specs it doesn't have to be changed.* If it doesn't, it should be changed.
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