Quote:
Originally Posted by Fluxcore
If they aren't, are the walls thick enough to prevent cavitation, or do I/we still need SCAs?
Thanks!
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Nice analytical deduction, but it has a problem. The 7.3 is not sleeved and does need protection. This block in 6.9 form soldiered on for many years of trouble free service. Then they bored it out, thinning the cylinder walls and creating this problem.
Cavitation wasn't even known until just a few years ago so you can drop the wet/dry sleeve analogy. The first 7.3 I ever saw was helping a friend in 1994 rebuild the engine in his 1989. He is a
service adviser and was at the time. Back then the official theory was casting flaws with sand somehow trapped in pores gradually falling out causing the leak. IIRC
This is an excerpt of an article on the subject I have:
Q: What is the history of cavitation?
A: From what I have heard the first people to realize cavitation was happening inside an engine was CAT. Supposedly in the 80's they started a study about cavitation. They were the ones who came up with SCAs and ways to protect high compression engines from damage. They discovered more heat and pressure in the cooling system actually slowed cavitation. On their engines that were run with smaller loads failed sooner than the more heavily worked engines. Also, if the engines were allowed to cool down more often they failed more quickly. Ford apparently didn't know about cavitation until the late 90's. My truck is a 92 and not in one place in the owners manual does it mention cavitation or any special coolant to use. A few years after having to replace the engine due to cavitation they sent us a letter in the mail alerting us to put SCAs in our coolant to avoid damage. In fact, I still have this letter and it is dated January 1998.
