I feel the same way. His RCA is very superficial and biased and lacks data to support his conclusions. You need to be unbiased for a proper RCA and CCN immediately jumps to inadequate PM without sufficient data to support this conclusion. CCN would be a lot more watchable for me if he took a root cause analysis training course and then made videos using RCA tools keeping his biases to a minimum.
I doubt CCN has had RCA training.
I sent an email to CCN to find out if Toyota gathers failure information from experienced and certified Toyota mechanics. I included very brief descriptions of other potential root causes for head gasket failure. If CCN has connections with Toyota, then perhaps he may be willing to pass along what he has observed along with a few ideas on the root cause. CCN has a shop to run and he has taken the issue as far as he can on his own.
When I worked in aerospace, we had division that performed all engine overhauls and technicians gathered data on which parts failed and how they failed. Engineering then analyzed the effect on bottom line profit when the customer paid for "power by the hour" or if we covered the expense of down time and engine replacement. Items that cost the company or our customer the most would get priority analysis to resolve. I would think Toyota has a similar program, and if so, I'm wondering about the process, hence the email to CCN.
If I was a Toyota engineer, I would propose acquiring a few engine blocks that either failed spec or were too close to failure and flow test them to see if the coolant hole between the left bank rear adjacent cylinders flows either more than or less than the other coolant holes in similar positions. I would justify an investigation if the same technology is employed on relatively newer engines with less fleet mileage or engines currently in the design cycle. Such engines most likely have lower design margins due to the need to raise fuel economy and power.
In my aerospace career, I was involved with an interesting and expensive engine failure. I designed parts that provided cooling air to High Pressure Turbine blades. Another engineer designed the blades. The engine spectacularly failed by burning the blades in its first test in front of our customer, the USAF. Management came to me and said, I was responsible for the failure because, (1) I designed the parts that sent coolant to the blades and (2) the blades passed flow tests thereby certifying them for use. I used test data on the parts I designed along with analysis of variation to show that statistically, the root cause of the failure was in the blade itself with better than 95% confidence. I proposed and conducted flow testing that isolated each cooling circuit within the blade because one of those circuits could well be the root cause. Testing determined that one location within the blade was flowing about 60% low while other portions of the blade flowed a little bit more than design intent, such that the total blade cooling flow was within spec and consequently a design issue was not detected during production. Management then gave me responsibility to redesign the blade, monitor production and test it. The next engine test proved there is adequate airfoil cooling with the redesigned blade. I also proposed crucial changes to the design process to prevent this kind of failure on future engine programs. Blades and vanes in a gas turbine engine have the greatest impact on program cost because the time to design, procure, machine and certify these parts is longer than any other part in the engine. Moreover, warranty costs are very high.
I have a strong interest in the CCN video as it brings up many memories of design issues and failures I worked on during my career. I studied internal combustion engine design in graduate school with plans to apply for work with one of the Big Three when I graduated 45 years ago. I changed my mind and went to work on gas turbine engines.
I strongly believe CCN has identified something that deserves a Root Cause Analysis that includes assessment of impact on current and future Toyota engine design and production. Afterall, Kaizen is a core principle in the Toyota Production System and obviously, any issue involving the engine block is expensive for either Toyota or a Toyota customer.
