Hi All, Some advice please: Which is the best engine coolant to use on my Detroit 12V71N 525 HP? There is a hand written note attached to the overflow pipe on the stbd eng. that says "Use Water only NO Anti-Freeze" Doesn't seem right to me & I will use a coolant. In Australia I have been told that Tectaloy will do the job. As brands vary between Australia & USA here are the ingredients of this product: Ethylene Glycol 280 g/L 10ppm Bittering agent. Thanks
Detroit Diesel makes an additive, that you add to the water, I would use that. It used to be called "powercool" I believe, call your local DD dealer for what the latest one they recommend is because I think they've changed names. If I remember correctly you added a gallon of powercool to 16 gallons of water. Depending on whether you need anti-freeze or just corrossion resistance there is a version of powercool you should use in the 71 series. See page 6 of the link below from DD's website. http://www.detroitdiesel.com/pdf/vocations/Coolant-Selections.pdf
We use water wetter in smaller stuff. I'd have to check what the guys use in the big engines. Google will get you to water wetter. It's not cheap, but it works well.
Here is a document that explains the options ... http://www.detroitdiesel.com/pdf/vocations/Coolant-Selections.pdf I use the Power Cool pre-formulated in the 5 gal pail (part number 23524677) in my 12V71TI engines. Mike
Just be aware adding anti-freeze/coolant will lower the specific heat capacity of water. In simple terms,the more anti-freeze/coolant you add the less capacity the water/glycol mix has to move heat. Pure water moves the most heat. Pure water specific heat is 1 calorie/gram C. or 4.186 joules/gram C. or we can convert that to any unit you like. There are other valid reasons to add coolant/anti-freeze/rust inhibitors.
those are interesting points, ...and there has occurred some very interesting/informative submissions on a discussion over here Coolant - scam? - Trawler Forum