Tag: Diesel

One of the most embarrassing things you can do as a car enthusiast is the so-called “money shift.” This sounds really dirty, but it’s simple. Often, you’re just trying to bang your car through its gears and accidentally grab a lower gear when you meant to hit a higher gear. This results in catastrophic damage and while there’s an abundance of videos on destroyed gas engines, less often seen is what happens to a diesel engine. Now, thanks to a YouTuber, here’s a look inside of a Volkswagen TDI engine that fell to a missed shift.

Volkswagen no longer sells diesel cars in America, but when it did, the company sold some great enthusiast bait. During the peak of the “TDI Clean Diesel” era, you were able to buy the Internet car enthusiast joke of a perfect vehicle. Yep, Volkswagen sold brown diesel manual wagons well into the 2010s. The Dieselgate scandal sullied the reputation of diesel worldwide, but plenty of these cars are still out there, though we’re one short after the driver of one TDI lunched their engine.

Missed shifts aren’t a new thing, but eventually, you lose count of how many people have broken apart gas engines in vehicles like Honda Civics and Volkswagen GTIs. Diesels are often remarkably robust engines, but they usually rev slower. I’m curious to see what happens to a diesel after a money shift and I bet you are too. Thankfully, the excellent YouTube channel I Do Cars has the diesel money shift gore we’re all looking for:

Our host, Eric, begins his video by telling us that it’s been hard to find one of these engines to salvage. He points the blame at the infamous Dieselgate scandal, which sent many of these cars to the scrapper. The rest remain in the hands of loyal TDI owners. Sadly, this engine wasn’t as lucky.

What you’re looking at here is a CKRA 2.0-liter four-cylinder common rail turbodiesel. Volkswagen mounted these in 2012 and newer Passats and when new, they made 140 HP and 236 lb-ft of torque. In the video, Eric says that this engine is a CJAA out of a Jetta from about 2010. In fairness to Eric, these engines all look pretty similar and the confusing engine codes don’t help. Both engines also have similar outputs as they both make 140 HP and 236 lb-ft of torque. Pictured below is what the CKRA looked like in a Passat:

And that naked engine by itself:

I was once a serial owner of VW TDIs from this generation and will say that Eric is absolutely correct when he says these cars drive great. If it weren’t for the low redline and the distinct engine noise you wouldn’t even know you were driving a diesel. These cars are also quick for diesels, too.

Sadly, Eric doesn’t know the mileage or service history of this engine, but there’s clear evidence that it had a very bad day. I mean, there is a giant hole in the block, after all. Even worse, the engine is so locked up from whatever caused that hole that Eric was able to sit on a breaker bar attached to the crank without moving a thing.

Without even getting into the engine, you can conclude that this little engine experienced an apocalypse. Still, Eric is on a mission to show us the carnage, so he gets working.

Most of the disassembly in these early stages is just a lot of getting through harnesses and lines without breaking them. Eric runs an auto salvage business, so he wants to save what few good parts this engine has left so other TDIs can live. Some things are hard to avoid, such as breaking VW’s notoriously difficult wiring harness clips.

Eric ran into a problem getting the injectors out and it was here that he learned the engine was a CKRA, but only because a CKRA has a different injector removal procedure than a CJAA. It takes Eric about 15 minutes of screen time to finally breach the valve cover. Surprisingly, the cams looked great and there was no sign of damage at the top of the engine. That’s neat!

Next, we move to dismantling the timing system. There was a bit of an oil leak, but otherwise, the failure didn’t happen here. Here’s where Eric points out the hilarity in VW’s engineering. At about the 19-minute mark, he removed all of the timing components and expected the inner timing cover to come free. However, he found that it was inexplicably secured behind the water pump.

Amazingly, carefully tearing down the engine takes so much time that we don’t even see the next bit of evidence of a failure until 23 minutes in. There, we see a second hole in the engine block with a piece of a connecting rod stuck in the hole. That rod sure got busy!

Later, Eric finds the head gasket in decent shape, but the cylinders don’t look too happy. One piston looks like it got really hot and one piston is hilariously deep in its cylinder. That’s probably the one that failed. But Eric doesn’t need to guess when he can just dig further.

As he continues, we find out that the oil filter is free of debris, but the same cannot be said for the oil pan. No major parts were found in there, but there was a whole bolt just chilling in the pan alongside smaller chunks of metal and a circlip. Eric notes that while the pan clearly indicates that a major failure occurred, there’s less debris than he expected considering the multiple sizable holes in the block.

It doesn’t take long to find the real gore. Both the oil pump and the balance shaft modules fractured into a bunch of pieces. The carnage is simply impressive and basically everything is broken in there:

An inspection of the balance shaft module shows that aside from being broken, it’s also severely bent and locked up. The damage in the block is as Eric says, “impressive.” A pile of piston pieces appeared and he found the other end of the connecting rod that punched a hole in the block.

Eric does get the engine to turn over after freeing up the destroyed cylinder three. He finishes the job by yanking all of the ruined parts out and doing an inspection. The rod bearings of all cylinders look okay enough, but the connecting rod for cylinder one appears to be bent slightly. Then we arrive at cylinder three, where all of the catastrophic damage happened. The rod fractured in multiple places, the piston broke, and bits showered out everywhere.

Meanwhile, the crankshaft had a ton of gouges and impacts, but the block took the brunt of everything with all of its splits and holes.

So, what happened here? Eric admits that he didn’t get the story on this engine. However, some investigating can rule out causes. There wasn’t enough water or rust in the engine for it to be a hydrolock event. There wasn’t enough oil or fuel in the engine either. Besides, as Eric notes, a fuel system failure would usually cause a melting condition in a diesel which didn’t appear here.

However, this engine did have a manual transmission bolted to it. Eric believes the only explanation that makes sense for the given damage and lack of other evidence is that dastardly money shift. He explains that a money shift in a diesel can cause the damage we see here, but also notes that diesel engines aren’t the same as gasoline engines.

If you over-rev a gasoline engine, you run the risk of valve float. This condition occurs when the valves do not retract and or seat properly before the camshaft lobes come back around. You can get valve float from the springs not being strong enough. You can also spin the engine over so fast that the valves just end up, well, floating. If you’re lucky, this just results in a drop in performance.

In a money shift event with an interference engine (that’s one where the pistons and the valves occupy some of the same space in the combustion chambers but at different times), there’s a chance your valves and the pistons can kiss, causing your valves to get bent. FCP Euro has a pretty good explanation by clicking here:

However, the valves on this engine look great. Eric believes this is the case since diesel engines already spin at slower speeds. At the same time, the valves in this TDI are more straight to the pistons rather than angled like the illustration in FCP Euro’s example. So he’s not too surprised the valvetrain survived the ordeal.

Even though this diesel died, there’s still some good to come out of it. Yes, the block is useless and many of the internals are too damaged, but Eric thinks many of the parts are good enough as cores and the head is good enough, too. Either way, it was pretty awesome to be able to see what the inside of a diesel looks like after such a dramatic event occurred. I’m definitely going to be thinking about this the next time I’m racing through some gears.

I also recommend watching more I Do Cars because all of Eric’s videos are a fascinating look into the terrible ways engines die.

(Screenshots: I Do Cars on YouTube)