Yesterday, I posted a message about soft vs. metal head gaskets. Thanks, guys, for all of the replies. I'll be going with the soft.A couple points were brought up though, that has led me to ask other questions. When I pulled the head, the bolts were not very tight, and it was easy to remove, which reinforces my leaking head gasket theory. The first thing I noticed was that the #4 cylinder had a lot of rust and corrosion in the combustion chamber. The other three were very black, full of soot, oil, and carbon buildup. After cleaning up both head and block with razor blade and wire brush I noticed some very minor pitting on both pieces around that #4 cylinder (coolant leaking into combustion chamber cause corrosion?). On the block, the pitting looked to be contained in the area between the cylinder and the two valves - the gasket seating area still looks to be flat. On the head, this pitting reached into the gasket sealing area in more than one place. This is my main reason for having the head surfaced, and I plan to consult the machine shop about how much needs to be taken off. I used a flat edge, and could not tell that either surfaced was warped, but I also figured a machinist could check for that too. My questions are: Is there a sealer (ie. copper sealant?) I can use on the surface between the head gasket and the block? I'm concerned with any imperfections on the block surface affecting sealing; and obviously, will not be able to have it surfaced while still in the tractor. Also, does anybody know stock valve-to-head clearance on these motors? How much can be taken off the head in total? how much can take off without having to do the clearance check with clay and all? Also, if I do check clearance with clay, what gasket do I use for the clay check? the old one? If I use the new one, won't it become compressed, and hinder sealing when I go to put it back together for good? Or do I buy two new gaskets (one for checking, one for sealing)? Anyway, I appreciate any advice one may offer. I just got the 8N, a hand me down, and while I also own a WD and am very familiar with it and other type engines, this is my first flathead. Once again, a great big thanks to all, this forum is a great resource. PS. Here's my theory on oil into coolant on a flathead (yes, it was oil [looked, smelled, felt, even tasted like oil ;)], sum total of about a half a cup when I drained the radiator. The tractor burns a little oil (blue smoke out tailpipe). I think this oil that is leaking into cylinder past the rings, which is burning and exhausted after the power stroke, is compressed and seeps past head gasket into waterjacket on the compression stroke. Just my own theory, cause at first I was realy scratching my head. I was thinking cracked block, but there is no water in the oil, and the thing runs like a top. OK, I'm done now...
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