The stall was exasperated by my ex-wife's stuff being moved into my work area. The cause was noble; She wants to sort through her stuff, separating those items she is moving to her place, and those that she is selling. Unfortunately her temperament towards such things is rather lax. Needless to say, her things are still in my work area.
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This is a nice protected area under a roof overhang. Very little rain gets into this area, and after covering the whole thing under a tarp, it should be fairly secure from the elements.
Now for the engine.
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While moving it out of the backyard shed, I am greeted with the jingle jangle of loose parts in the garbage bag used to wrap the engine. Without looking at the repair manual it was fairly easy to determine they were part of the transmission shifter linkage.
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Earlier that day, for some inexplicable reason I purchased a file set. After a few failed attempts, it occurred to me that I should try to file off the remaining rough part, leaving approximately 1/3 of the bolt head.
Then, using a hammer and punch, strike the bolt head to give it a counterclockwise rotational force. After a few strikes... Success! It rotated! A few more pings and the bolt was rotating with no more pressure than that supplied by the tips of my fingers!
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The bolt head claimed four drill bits, several grinding wheels and even a diamond Dremel grinder. It was time to go.
Now, with all head bolts out, the next little roadblock presented itself. The front piston seems to be somewhat... stuck in the cylinder. It will move in and out of the cylinder by an inch or so, but that is it.
Next up - More engine disassembly.