Cleetus McFarland Tears Down Blown Engine of Auction Corvette
Engine in C6 Corvette failed during a hard track pass, destroying bottom end of 5.3-liter mill.
Garrett Mitchell, host of the Cleetus McFarland YouTube channel, recently had the engine in his “auction Corvette” fail dramatically on the drag strip. As expected, he chronicled the tear-down process of the engine to share the carnage with all of his fans and followers. As you might expect, the damage in terrific in a bad way, with broken pistons, broken connecting rods and random bits of metal scattered throughout the engine from top to bottom.
The Ill-Fated Run
The video begins with Mitchell showing us how much metal was in the oil sprayed across the windshield when the engine blew, followed by a look at the run during which the engine failed. We watch the run from the in-car camera that is pointed at Mitchell, and things appear to be going smoothly until smoke begins to stream into the cabin. He struggles to keep the car straight as oil covers the windshield and smoke fills the cabin, but the incident ends without any further issues.
However, there was no doubt that the engine was toast, so Mitchell and his crew made a video of the tear-down process, allowing us all a chance to discover the amount of damage right along with the guys from the Cleetus McFarland channel.
The Tear Down
The “auction Corvette” is powered by a 5.3-liter truck engine with more than 200,000 miles, fitted with a custom turbo setup that puts the snail up in the air over the engine. This looks cool and creates the ability to shoot flames from the boosted engine, but the downfall is that when the engine fails, it vents the oil across the windshield.
The damage is apparent from the amount of metal in the oil on the windshield, but the fact that the oil looks more like dark silver paints drives home the fact that there is massive internal engine damage. The engine is seized, so they can’t turn it over to remove the flex plate, so they are forced to remove the torque tube from the transmission to pull apart the driveline.
Once the turbo setup is off and out of the way, we can see that the crank balancer has come apart, serving as another sign of things to come. From there, the crew removes the steering rack, providing just enough space to pull the engine forward and up out of the car.
Inside the Engine
With the 5.3-liter engine hanging free of the Corvette, the team begins to survey the damage. In looking through an exhaust port on the cylinder heads, we can see that there is a piece of piston holding one of the valves open, at which point the team discusses how many pistons they expect to find broken. Mitchell predicts two while the others all predict three, and it looks like they might all be wrong.
When the first head comes off, there is one piston that appears to be broken free of the rod, sitting near the top of the bore. When they move around to the other side, we can see where one piston hit the valves, another piston cracked in half and one piston is completely gone. In the cylinder where the piston is missing, most of the rod is gone as well. There is also significant damage to the head, with parts of the pistons jammed in the valves.
As Mitchell puts it, “it was low on oil pressure, it was high on boost, things were getting pretty intense”. As a result, pistons disintegrated and this engine turned its final revolution. As they pull the oil pan, they find many of the pieces of the rotating assembly that were missing from the cylinders, including many piston chunks and a few large parts of connecting rods.
Mitchell jokes that “the cam looks alright – I see some score markings. We can sand’er down a little bit”, but it is jammed in the block so hard that even beating one end with a mallet and part of a broken rod don’t budge it in the engine.
In the engine, Garrett Mitch proclaims “verdict is, this engine is blown.” However, his plans to find another 5.3-liter truck engine, buy the parts needed to reassemble the turbo build and get the auction Corvette back on the track.