Head is off at the machine shop and I'm praying for a quick turn-around. Cleaning the block yesterday I scrub off all of the carbon build-up and there's one chunk that won't wipe away (also notice the pitting):
Finally I move on to the others and move that piston to the bottom of the cylinder and realize that I may have overlooked something during my initial inspection. After cleaning it up I was able to find this:
This is the cylinder that the spark plug broke on
My nail *slightly* catches on a few of these marks unfortunately.
At this point I have to look at the facts:
-compression was good in this cylinder
-leakdown test showed leakage in the valves, not the rings
-while not the whole problem, this may have been contributing to the oil consumption issue.
DSM'er in me (and my wife) are forcing me to finish fixing the head and spend the couple hours it will take to re-assemble it and get it back on the road. I cannot afford the downtime required to fully fix it right now; the block is already .020" over and will need to be sleeved if it comes out again. Once it's back together I'll re-test compression/leakdown and watch oil consumption and then keep an eye out for a good core to get sleeved.
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