A DT466E engine failure with progressive damage

Hello, everyone.
Today I wanted to post a short note about engine problems and progressive damage. I recently finished an inframe rebuild on a DT466 that suffered classic progressive damage. What happens is that a major component will fail but as the truck still runs, the customer will keep driving, causing additional damage until the engine finally quits running.
When the truck came in to the shop, the engine would not run. I was told that there was coolant in the oil pan and that another shop had looked at it and decided not to tackle the problem. I proceeded as if a standard inframe was needed, but as soon as I removed the valve cover, I knew I was in for more. An engine with a badly overheated component that fails catastrophically has a distinctive odor, and that is what I smelled inside of this one.
The first indication of a serious problem was seeing that the #3 exhaust pushrod was bent into a pretzel and the cam follower guide for that cylinder was broken. This problem is not uncommon in the 466, and it meant that the cam would need to be replaced, adding about 12 hours to the inframe job. When the head was off I expected to see some damage, but the #3 piston crown was completely melted and a large piece of it had been banging around in the cylinder. At this point I realized the truck had been driven for a while after the problem started, and I was prepared to see more damage as I continued disassembly. I was not prepared for what I saw next. That #3 piston was seized in its liner was not a surprise, but seeing the extent of damage to that liner was. It was split lengthwise in two places and had to be cut off the piston in order to remove the rod. A picture of what was left of the piston is shown below.

DT466E piston that suffered progressive damage compared to a (relatively)  undamaged piston

The failed piston had spit metal into all the other intake ports, so many of the valves were leaking; stoddard solvent ran out the valves almost as fast as it could be poured into the port, and #3 exhaust valve was bent. I also found that the turbo impeller had seized tight, but luckily had not made contact with the housing.
So, my idea of what happened was that the #3 cam follower failed and caused a dead miss, but the driver or his company decided to finish his delivery route. Soon the valves in that cylinder wouldn’t open properly, and the piston started to overheat. The liner may have overheated to the point where the o rings failed, or maybe the piston expanded to the point where it split the liner. Whatever happened, coolant poured into the oil pan and damaged progressed quickly. The turbo didn't last long running its bearing in coolant instead of oil, and it failed, drastically reducing power. My guess is that this is when the truck was finally stopped, or maybe the driver just got tired of all the hammering the engine made and the low coolant and overheat alarm going off.  Or maybe the smoke cloud tipped him off to a serious problem.
I have replaced several failed cams in the 466 engine, and most drove to the shop. All that is usually required is a cam change, a couple of followers, and pushtubes. Although not an inexpensive repair, it is much better than risking the type of damage seen in this case. I have never seen this kind of progressive damage after a cam failure, so the vehicle must have been driven quite a while after the problem was realized. I understand the desire to finish a delivery route with an unexpected engine problem, but at some point I would think one would have realized this problem was more than a failed injector or another fairly minor problem.

A list of parts needed illustrates the extent of damage the engine suffered:
• Inframe kit: liners, pistons, rings, and bearings, and gaskets
• Camshaft, 2 cam followers, and 2 pushtubes
• Injector for #3 cylinder
• Intake and exhaust vales for #3 cylinder, plus machine shop work to regrind the valve seats
• Turbocharger

In addition, all valves had to be removed, the seats cleaned and relapped, the intake manifold and inlet side air-to-air tube had to be cleaned.

New writers needed here

Hello, everyone.
I would like to extend an invitation to anyone who would like to write a post for this site.
Outside writers will inject some new blood and capabilities into this site.
Of course, you will be credited as the author of your post. Just send a sample of your writing to my email ( a link is provided in my complete profile), or send a link to something somewhere else. You can then write your post on this site, or send it in and I will post it for you.
If you want to continue to write after the first post, you could be added as a second editor.
Thanks for reading
Bruce

Mechanic shortage?

I ran across a post dated March 11, 2013 that starts as follows:

In an effort to combat the rising technician shortage in the trucking market, TMC has created a technician career path development task force to help retain, recruit and promote quality technicians. The new task force debuted Monday at TMC’s Annual Meeting in Nashville, and was led by Brian Mulshine at Navistar and Chris Harvey at PACCAR.  
http://www.truckpartsandservice.com/tmc-creates-technician-career-development-task-force/

Technician shortage? Really? Much has been made the last few years about the shortage of mechanics becoming worse in the near future. My question is, if there really is a tech shortage, how come wages aren't going up? Look at the median technician wages for the past 5 years:
http://www.jobgeeks.com/jobs/truck-mechanic/

Now, the chart caption says that wages have gone up $3010.00 from 2007 to 2012. But I submit that looking at the numbers in this way skews the facts. Why not compare wages to the peak in 2008, before the bottom fell out of transportation and nothing was on the road? Looked at this way, wages have gone up just $1470.00 in 4 years. If the industry really wants to attract new blood it will need to increase wages more than that. More importantly, quality people will need to be attracted to education programs that teach the skills actually needed at the entry level. For instance in my opinion, teaching engine building in a truck mechanic program is a waste of time. True, basic engine function and an overview of troubleshooting is necessary, but what is really needed is a deeper understanding of brakes, clutches, driveline, and especially electrical/electronic systems. In other words, how to do the bulk of the work seen in a repair shop.

If smart, technically savvy people are going to be drawn into the industry, they will need to be attracted from those now going into other technical fields, fields where one may not need to climb around on or work under dirty, dripping equipment on a daily basis. The only way to do that is with higher pay.

I think the shortage is a lack of good people who will work for the wages offered, rather than a shortage of good techs.

We as mechanics are part of the problem. Every time we misdiagnose an electrical problem because we do not understand how a relay works, we give our employer a reason to realize less value in what we do. If one of us feels he can do his job without understanding how to use diagnostic software or online resources, he probably deserves less pay. If we expect our employer to increase our pay, we need to become more enthusiastic about keeping up with new technology.