To flush or not to flush (coolant), that is the question

[HamSkoolie]

Originally Posted by Booyah45828

FWIW I'm not aware of chronic cavitation problems with the t444e. The 7.3 idi that it replaced was known for it, but not the t444e.

Everything I've read on the 7.3 Power Stroke says it suffers from "cavitation" just like the preceding IDI version. Sources that also discuss the DT444E make no distinction between the two when it comes to cavitation.
Considering the expense of a rebuild ($14,000 installed with 5 year nationwide waranty) I'll continue to do everything I can to ensure no "cavitation" occurs.

[Booyah45828]

First off, any diesel can cavitate when lacking the proper additive to prevent it. So every diesel can "suffer" from cavitation.

The 7.3 IDI is notorious because the block casting was unchanged between the 6.9 and 7.3, but the 7.3 had an additional .110" bore size, making the cylinder walls particularly thin compared to most diesels. The thinner the walls the more easily cavitation can occur. 6.9 idi's weren't nearly as troublesome.

Powerstroke cylinder walls are a lot thicker then the 7.3 IDI, and therefore don't have near the cavitation issues.

7.3 IDI's were so bad with cavitation most rebuilds were sleeved all 8 instead of overbored, as the chance of having a bad cylinder was too great. Powerstrokes don't have that issue.

[HamSkoolie]

While the Power Strokes aren't "that bad" compared to the IDI's (problem addressed), they are still highly susceptible to "cavitation". Since the result of a "cavitation" failure is rebuild or replace, every step should be taken to be nice to the system. As the vast majority of non fleet (and even some fleet) users do not stay on top of maintenance.

Just this week I was asked to look at a 3 year old SUV that was having driveability issues and the owner thought it was the transmission because the RPM's were fluctuating and the car didn't seem to accelerate properly.
I started with a fluids check.
Trans fluid pink, sufficiently full for a cold check, not burned, no grit
Engine oil, tip of the stick showed mild corrosion discoloration & ZERO OIL
Added THREE QUARTS to the 5 (with filter change) system.
Vehicle test drove just fine and transmission fluid level was perfect after warmup and recheck.


Million mile of 500k mile ELC's that eliminate the "cavitation" issue are well worth it and in THIS mechanics opinion NOT an option.


You may have noticed the use of quote marks around the word cavitation. While it is the proper word, most people think of cavitation as Webster's first definition. The one that applies to ships propellers and other moving structures in a liquid with the cavitation bubbles acting abrasively upon the structure. Webster's definition 1 is:

1. The sudden formation and collapse of low-pressure bubbles in liquids by means of mechanical forces, such as those resulting from rotation of a marine propeller.

However, in the context of the 7.3 cooling system, Webster's 2nd definition is the justification for the use of "cavitation".



2. The pitting of a solid surface.