A customer had his 2006 Z06 towed to our shop with what he thought was a blown head gasket. The outcome was actually much worse. Upon closer inspection looking under the car we noticed that part of the engine block had pushed out and the motor had way worse damage. We took out the oil pan plug and got some oil, but mostly coolant –not good. Taking the heads off the engine it looked like the piston had disintegrated and all that was remaining was the wrist pin. The chamber in the head looked like hamburger too.

This car only has 11,000 miles on it so we were a bit baffled as to why it would have such a catastrophic failure. Upon doing some research we found out this is actually a known problem in the Z06. It turns out the valve guides can go bad prematurely and cause a valve to stick at high rpm, which then causes the piston to smash into it and lots of fail to happen. You can see in the pictures below the cylinder walls were even cracked and pushed out when this happened.

We are still weighing some repair options with the owner but if you own a Z06 you might want to have this checked out before something happens, because it’s not a cheap repair.

The car in question. 2006 Z06 with only 11,000 miles.

Draining the oil but getting mostly coolant.

This engine has hollow sodium filled valves. This is the valve that stuck and then broke off in the cylinder causing the damage.

The piston broke into many pieces and all that’s left is the wrist pin. Notice the cracked cylinder walls too.

Here are the few pieces of piston we have found so far.

The inside of the cylinder head chamber got tore up pretty bad too.

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