Doing some investigation following the engine pull and discovered a clogged heater core. Sorry yanks but I don't think I have ever actually used the heater here in FL. I am wondering if this contributed to engine demise. The engine had about 100k and did not overheat. It lost compression in #5. Looking at the wiki diagrams its not very clear but I don't see any obvious reason this would cause a hot spot. At the same time #5 is the weak link w/o heater flow. It could easily be more clear in a different diagram. Has this come up previously or maybe a known issue?
Follow Ups
Considering the complications caused by clogged heater core - shaggee15:35:51 09/14/15