Wow, Thanks for that walk thru. This engine was stock I presume and do you know if the head gaskets where the originals? also the head bolts looked to have 0 stretch is that correct? Did the oil cooler/egr cooler need to be replaced and if so did ether or fail and cause the head gaskets to fail? Sorry for all the questions but it's one way to get the answers right?
The headgaskets were original. There is never any "visible" stretch. Think of the headbolts not as bolts, but as springs. Any time there is multi-layer gaskets, movement is designed in. The headbolt "springs" allow for that movement, but still maintain clamping force. The "stretch" that everyone refers to is the bolts inability to maintain this clamping force. Kind of like springs losing their "springiness". And no, unlike popular opinion, the egr cooler wont cause headgaskets to blow. If coolant gets into the cylinder, rods will bend or pistons will break first before the gasket will blow.