Ka-Boom! Diesel Engine Explodes On Dyno, Throws Piston into the Stands

No, this is not a scene from a movie.

In 1998, Peter Bernstein published a noteworthy bestseller by Peter Bernstein titled Against the Gods, the Remarkable Story of Risk. The author's premise was that in whatever endeavor one undertakes, there is risk involved and we need to learn how to manage it. No one is infallible when predicting outcomes because there are always variables outside of our control. In short, risk is a part of business. There are no sure things. As Robert Burns noted in his Ode to a Mouse, “The best laid plans of mice and men often go awry."

This book came to mind when I read a recent Truck Trend story about a 12-valve Cummins diesel engine that blew up on the dyno in a somewhat sensational fashion. It didn't just throw a piston; it threw a piston into the crowd.  

Competition pushes people to discover the limits of their equipment. Nevertheless, these efforts always involve risk. You can choose to play it safe and minimize risk, but you won't bring home any trophies.

The explosion took place a few weeks back at the Ultimate Callout Challenge in Brownsburg, Indiana. The team Power Driven Diesel had its truck named Godfather up on the dyno. They were looking for spectacular numbers. Instead they experienced a spectacular debacle.

According to the story by Monica Gonderman, the truck's main engine had been having trouble during the drag racing portion of the event so they replaced it for dyno day. Evidently they had a small fire a couple hours before their turn on the dyno, but must have felt they were good to go. 

They were aiming for an earth-shaking 3,000 horsepower, which they hoped to achieve with a little squirt of nitrous. Having hit 2700 hp a week earlier, they were feeling upbeat about it. Gonderman writes:

After shifting into fourth gear, the truck was under full power and pushing probably 250 pounds of boost. It was ripping through the pull nicely--until it wasn't. The internet reports that the truck made 2,369 hp and 3,039 lb-ft of torque before exploding. 

As we said at the outset, there is always risk involved, especially when you are pushing the envelope. The truck experienced serious damage as parts flew everywhere. The piston landed two rows in front of a guy shooting video. 

The PDD team seems to have been good sports about it all, because they offered to sign engine parts as souvenirs for those who witnessed the calamity. Todd, the man in the driver's seat, said the reverberations from the explosion felt like what you might feel when surrounded by an exceptionally good sound system. Good vibrations? 

On May 23 the Power Driven Diesel team posted a video about the event on YouTube and has already had over 200,000 views. You can watch it here. 

You can also check out the Truck Trend site to read more and see a gallery of photos.  

NOTE: This coming weekend it's the Daytona Truck Meet at Daytona Beach, from June 10 - 13. Will we see you there? 

Three Engine Options for the Current Jeep Wrangler, Compared

Once you've been around the truck and auto magazines a while, you'll begin to notice the names of many of the writers and editors you've been reading. One of these is Christian Hazel, whose writings have appeared in a range of our favorite magazines including Four Wheeler, Diesel Power, 4x4 Garage and others. He got his start writing for Petersen's 4-Wheel & Off-Road magazine, ultimately becoming their tech editor before taking the reins at Jp magazine.

In short, he's been immersed in the off-road culture for more than two decades and has a keen eye for the nuances of various off-road machines and the engines that power them. When I saw this story the other day comparing the three engine options for the new Jeep Wrangler, it didn't surprise me to see who wrote it. The article is titled Jeep Wrangler JL 2.0L vs. 3.6L vs. 3.0L. Hazel has an opportunity to put to the test three Jeep Wranglers to decide which engine works best. Here's the setup.

"Which is better for a Jeep Wrangler: the 270-hp/290-lb-ft 2.0L eTorque inline four-cylinder, the 285-hp/260-lb-ft 3.6L Penta star V-6, or the 260-hp/480-lb-ft 3.0L EcoDiesel V-6 turbodiesel? (Hey, the V-8 Hemi isn't out on the streets just yet!)" 

The Jeep name is more than a brand. For many it's a way of life. But just as lifestyles vary, so the engine options add versatility to this round of Wranglers.

As a Jeep journalist for more than two decades he's probably been asked a hundred time, "Which the best this or that?" This time around, he's been handed the opportunity to compare a trio of Jeeps, or rather, engine choices. 

Wrangler with 2.0L Engine 

The first engine Hazel put through the paces was the 2.0L engine. "In terms of performance behind the wheel, the 2.0L is my personal choice of engine. It is linear and seamless. The turbo bites into the power delivery way down low, providing a lot of gooey torque that gets you up and off the line in a hurry. There isn't the exhilarating top-end kick that you get from the 3.6L gasser, but from the driver's seat the Jeep feels like a spitball greasily being blown through a straw as it maintains speed on grades without downshifting or accelerates into traffic or for passing without a lot of vibration and fuss." 

I love the descriptions. The prose seems more like classic literature than gearhead talk. 

Hazel likes finds this Jeep to blend power and drivability in a single package. The mpg is decent, too: low 20s on the freeway.  And when it comes to rock crawling, he points out that it handles differently from the other two. It handles smooth, though, and offers "perfectly good off-road capabilities."

Wrangler with 3.6L Penta star Engine 

"Personally, this would be my last choice," Hazel say. 

As with the other two options he begins with a detailed breakdown of Penta star's on-road drivability. It's got power, no question. And when it comes to fuel economy it's no slouch either. By the time you read his description of how this V-6 tackles off-road terrain, you almost get the feeling it's his favorite. If I'm correctly reading between the lines, all three of these Jeeps have something to offer.

Wrangler with 3.0L EcoDiesel Engine 

At the Blue Flame we're partial to diesels, therefore I was most interested in see what Hazel had to say about the 3.0L EcoDiesel.  Here's how he describes this breed for on-road drivability.

"If the 2.0L feels light and airy to me and the 3.6L only less so, the 3.0L EcoDiesel makes a Wrangler feel as rooted to the ground as the Rock of Gibraltar. For me personally, it'd be a close Number 2 choice right behind the 2.0L four-cylinder. Without looking up any weight differences and going by seat feel alone, the diesel Wrangler feels heavy. That said, it's also got liquid squirt for days. Just mash the throttle at any speed, and those 480 lb-ft plant you firmly in the seat as the Jeep shoots forward like water out of a firehose. It's addictive, especially when you're traversing hilly, mountainous back roads."

He describes the acceleration as "velvety smooth" and that when driving you'll look down at the speedometer and find that you're going faster than you realized.

 In the realm of fuel economy he acknowledges it to be good, but that it's not so significant as to be the reason to purchase it. Yes, it has better fuel economy than the other two, but you want to purchase this puppy for its other advantages.

As for off-road action, he's very direct. "It's a tractor. It's simply a silly, fun, no-brainer tractor that you toss in the lowest gear and idle cleanly and smoothly through whatever obstacles are before you. When it comes to rockcrawling or navigating technical trail systems in low range, there's simply no comparison in tractive power application. The 3.0L V-6 EcoDiesel will just smoothly chug you through and cleanly let you modulate the throttle on shelf and other climbs."

After making several other statements of this ilk the bottom line is that it has only one downside: the sticker price. He immediately adds that once you are in the driver's seat you will never give that a second thought.

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There was a lot more than what we've referenced here. 
Be sure to head over to the Truck Trend site and read the full story.
Here is the URL:

http://www.trucktrend.com/features/jeep-wrangler-jl-engine-differences/