With the major metalwork done on the 240Z body, I spent some time on the engine rebuild:
A good friend and fellow car crafter gave me this Kleen-Flo parts cleaner. Although he had finished with it, it still had a lot of use left in it. It also smells BAD, so he brought it over for me to use!
The short block was in great shape, so I left it as is. The cylinder walls were perfect, with no carbon ridge and very little buildup on the cylinders. I cleaned what was there and went ahead with the new gasket rebuild:
As the engine has sat for nearly 15 years, a squirt of WD40 into each cylinder will ensure we don't get a dry start. I had previously rotated the engine to ensure nothing was stuck.
On the top end, I tested the valve seals earlier by squirting gas into the intakes with closed valves. Not a bit of it leaked after weeks of sitting on the bench!
The valve relief pockets, valve bottoms and the mating surface were all cleaned and prepped for re-assembly:
After using scrapers and wire brushes on any head surface, I've learned it's a good practice to go over it with a hard block and 180G then 220Grit papers - in a cross-hatch pattern. This shows up any imperfections and gives a clean - and flat - surface to ensure a good seal.
A good cleaning with compressed air ensures there's nothing left to contaminate the engine.
Just before installing the head gasket, I apply a sealant to any join areas, just to ensure a leak-free build. Nothing worse that a pesky leak on a freshly rebuild - and detailed - engine!
With the head carefully lowered onto the block, the hex-headed head bolts ( that's a mouthful) were coated with anti-seize, then hand threaded to start them. Finally, they were torqued in three stages: 25, 35 and 47 foot pounds, starting from the center two and working outwards and alternating sides until all were torqued. Once I have them all torqued, I like to leave them for a while before re-checking them once prior to buttoning up the valve cover.
With spring finally springing, I was easily distracted and decided to get my summer cruisers out of their cold storage and into our attached garage so they'd be ready to go whenever the mood strikes!
This is were all that work pays off - next year I hope to be able to put the 240Z into my fun-car rotation!