Discovered cracked Castech heads right at the start of the COVID lockdown (mid March). Ordered a pair of refurbs from a place in CA that got good reviews. One was a castech, the other not. Took my sweet time installing, some weeks I wouldn't even work on it. Buttoned back up mid June and drove less than 500 miles by mid July. Noticed coolant level still lowering...not good. Emptied new catch can - milkshake. Pulled valve covers - milkshake.
Depressed and dejected, I let her sit until this week. I didn't know at that point if I did something wrong installing or got bum parts or both.
Got some coolant dye for Dex and circulated it. Pulled the valve covers again and cleaned up the heads so no dye was visible. Pressurized the system and waited. Found a crack in the Castech refurb in the same damned spot as the original head. Very strange. Waiting on response from vendor about warranty replacement. Sucks, but I'm still not in a hurry.
You can see the crack under the blue bubbles.
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