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Old 01-13-2026, 12:25 AM
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JBanna JBanna is offline
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Join Date: Jun 2003
Location: Spokane, Washington
Posts: 404
Default Blown Head Gasket

Hello again experts! I had an issue with my engine, with valve clatter and a serious drop in oil pressure at low rpms, but only under load. I decided to pull the heads after compression and leakdown testing showed a problem with both my # 4 and 6 cylinders, so I pulled that head and found a blown head gasket between their exhaust valves, which explained the compression problems, but what could have caused this? The attached photos show the blown gasket and the condition of the cylinders, all of which look undamaged...thoughts?

Thanks again to all!

Joe
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78 White T/A, Carmine interior, Fisher T-tops, WS-6 package, 3.08 gears, a/c, rear discs. Original 403 with 300,000 miles replaced by new Pontiac 455 (roller everything, 6x-4 heads, Performer manifold, Hooker Headers, Hughes converter, Cliff's Q-jet) - I only get 12 mpg!