Ford later issued a bulletin to address that, and problems decreased dramatically.Īs Bob stated, SCA's are one method of inhibiting cavitation by providing a barrier on the coolant side of the cylinder wall. FWIW, the Ford 6.9L and 7.9L IDI's originally had serious cavitation issues because Ford did not initially require (or add) SCA to the coolant. Unlike gasoline engines, all diesel engines experience some level of inherent cavitation, some worse than others. Water/coolant enters the cylinder, and thus we have engine failure (usually via hydrolock). Eventually the prolonged pitting become a hole. It is this implosion against the metal surface that causes the pitting to form in the outside of the cylinder wall. The bubbles in diesel cylinder wall cavitation don't explode, they implode due to pressure. Much like if you filled a plastic liter pop bottle up with water and rapidly flexed the sides of the bottle back and forth with your hand. Where diesel cylinder cavitation is concerned, the bubbles are formed by the rapid flexing of the cylinder wall liners as the high compression, high energy diesel combustion process takes place. I am also a Mechanical Engineer with a background in Materials Science who has studied cavitation in cylinder walls and water pumps. I've operated and maintained a large fleet (100+ vehicles) of International/Ford 7.3L Powerstrokes. I worked with International during their cavitation crisis of the 6.9L and 7.3L IDI, helping to write bulletins, provide technical field data, and testing several different types of coolants, SCA's and mixtures thereof. To give you a little background, first let me say that I've had extensive training and education in the field of coolants, some by the coolant manufacturers themselves. I think Bob realizes that much of his information is out-dated, pertains to certain engines other than our Powerstrokes, and is just plain wrong. I've been getting lots of PM's about Bob's coolant/SCA article (the sticky that was closed), and I would like to address a few things to help folks better understand. The reason I post Gooch's response in its entirety is because I do not want to edit anything and possibly change how the information is meant to be applied.Īs you can see, the info taken by and of itself is easily understandable without the "backstory" regarding the reason for the post. Keep this in mind when you see references to other people and topics that haven't been addressed in this thread. The following is an excerpt from a thread regarding questions that arose in the thread, where Gooch addressed those questions and issues. I changed it after 100k miles and when I examined/tested it it didn't need to but I was already needing to drain it for other work.īelow is a cut/paste of info that is out there in search land, hopefully answers some of the coolant questions 4 gallons and 4 gallon of distilled water and this coolant is good for MANY, MANY years. There are some other SIMILAR coolants like fleet final charge and other off brands at truck stops but I personally use Caterpillar on my equipment, and used Zerex on my previous 6.0l (its harder to find in my area) so after research I found Rotella by Shell at a local farm store for $15 a gallon of concentrate. *With that being said there are REPORTS of people draining and refilling every 30-50k have success but 8 gallons of coolant is expensive.ģ-Most go with ELC Rotella, Zerex, or Caterpillar are my top three. It gels up and clogs the coolant passages in the oil cooler which restricts the coolant in the egr cooler and this causes the reduced coolant through the egr cooler to get super hot and gel up further. I was told that it was installed with the proper procedure making sure that 100% of the water was blown out of the system before installing (BTW the guy was a nut on changing all fluids before required).Some considerations are needed with coolant and the 6.0l.ġ-Never put regular universal green-It can handle the pressure and can lead to damage through cavitation.Ģ-Ford Gold is a risky coolant and generaly speaking is to be avoided. I currently have this coolant in my vehicle, purchased the truck used with 170,000 miles on it about 2 months ago. Higher flash-point Evans coolant just seems like such a good idea on these trucks with their EGR coolers and temperamental head gaskets. I'm just thinking less steam = less pressure. Seems to me with a lower flash point there will be less possiblity of pressure lifting the heads or blowing the head gaskets. To much heat (exhaust gases)and not enough flow (coolant) equals small steam explosions which is what throws the coolant out and all over your engine.Įvans coolant has several properties which help prevent these little problems. From a physics point of view, Ford/IH or both should know better than this. The EGR cooler is a screwed up design no matter how you look at it.
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