Man... I am not having a good week...
I just finished building another 2.4:
Everything was cleaned and machined to my specifications by Gosh.
Crank was balanced and polished.
Custom pistons had the PWC I wanted.
I ground the rings for my usual end gap.
Valve clearance was clayed and several thousands better than I required.
Correct clearances (plastiguage) for main and rod bearings, correct side clearances (feeler guage).
Graphite Moly used on the bearing surfaces, 20w 50 dino on the rest.
PermaTorque headgasket with A1 studs torque to 100lbs with moly in 6 stages.
OEM 2.4 cam gears (no degreeing required) and timing belt, alignment and tensioner gap was correct after spinning, waiting a hour and respinning.
Primed oil pump with grease.
Everything spun nice and smooth.
Filled the engine with straight 30w dino oil for break-in.
Fired the car up, verified oil flow at the head.
Let car warm up to 200 degrees.
Took it out and began to break in the rings. I was taking it up to ~12 psi, at 4 to 5000 RPM and then engine breaking in a low gear. Car felt really strong. After about 5 minutes of this I was approaching a T intersection and popped the clutch in and proceeded to coast the last 200 feet. It was at this point that the unmistakeable sound of rod knock started. Very quietly at first but rapidly increased in noise when suddenly I heard a sick metallic screech and the motor seized. Thick black smoke was everywhere, pouring out of the head evac.
Flash forward to last night. I removed the oil pan to get a better look. Behold the carnage:
Look at the heat discoloration!
The crank is just FUBAR...
This is the shot that really scares me, because it appears that for some reason the bearing was not getting oil. looking up the journal it appears to be dry.
I've only built a handful of 4G engines, so I am most certiantly not an expert. Still, does this seem rather odd? I am trying to figure out what I did wrong on this engine or if it was a clogged oil journal in the crank or block?
Anybody have a similar situation with a freshly rebuilt engine?
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