Hi, guys. I'm currently trying my first engine rebuild as part of the process of a (slow, too slow) GTV6 restoration. The engine didn't run for +/-10 years and both heads and block surface presented pitting along their surface as a result of that inactivity. After cleaning everything well, resurfacing heads... I need your opinon on the block.
After spending several hours of intense cleaning, the block surface is smooth when you slide your finger along it, except at the part along the six water passages (surrounded with red) that presents noticeable pitting.
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Measuring flatness with a straight edge, at those points I can slide the 0.05 mm gauge (0.002 inches) and not the next one (0.1 mm / 0.004 inches). Since 0.05 mm / 0.002 inches is the maximum recommended at the manual, it seems that the surface flatness is beyond spec just a bit. What can I do at this point? Several ideas come to my mind:
a) Throwing away the block. I don't really want to if I can avoid it.
b) Resurfacng the block is not an option since the machinist couldn't remove the studs without risking the block.
c) Using a very fine grit sandpaper / steel wool and, pressing it with some flat surface and extensive care, eating some 0.01 mm all around to keep it under specs.
d) Fitting the gasket hopěng that it will seal the imperfections. That's the easy one!
e) Using some sealant with the head gasket in the pitted area to help it.
f) Using some metal epoxy (JB Weld or similar) at the pitted area spreading it with some razon edge and fine sanding it until getting it perfectly flat. This doesn't seems a crazy option since the area doesn't support a great temperature or pressure, but still have serious doubts about it.
Too many options, too many doubts...
Have you faced this situation before? Which way did you take? Opinions and experiences are really appreciated.