Wow, it has been so long since I worked on my 2N that I had to look at my last post to remember where I was. Seems that back in early December I had good blue spark, good compression (OK, Dell was not impressed with 100 psi on a new rebuild), and I had some combustion going on, but the tractor would not start. Just a lot of popping and smoke when the starter was turning the motor. What could be the problem? We sorta narrowed it down to a problem with timing, possibly a mismarked camshaft timing gear (I did install a new one with my rebuild.)Dell and David – OR explained how I can check this; not as bad as putting the engine back on the stand, but still a big pain! And back then I new I would not have much time to spend on this project until March, so pulling the head was not an option at the time. However, one other suggestion was to try to run the tractor on starting fluid. I had time for this, so I tried it and it worked. The tractor ran just fine when starter fluid was sprayed into the air intake of the carb. But it would not run without the starter fluid. One other detail I had not made note of before. When I have gas in the carb, the gas pours out of the air intake. These two facts led me to decide to rebuild the carb before I pulled the head. Sometime last month I rebuilt the carburetor on the kitchen table while my wife was in town. Today (finally) I had the chance to put the rebuilt carb back on and try again. Still no luck. In fact, things have gotten worse. Gas still pours out of the air intake. But today the tractor will not run on ether. I checked a couple of other things. The voltage at the coil does not seem right. When the points are open, I have > 12V, but when the points are closed, I have less than 3.5V. Actually, I open and close the points by bumping the start button. Then I put my meter on the coil and then turn on the key. When the points are closed, I get about 3.2V at first, but it bleeds down to about 1.8V. Does this indicate a bad condenser? Dang, I didn’t have another one to test with. Then comes the killer. I checked my compression, and I’ve only got about 70 psi in each cylinder. I hope this means a stuck valve, and it might explain the tractor not starting on ether, I suppose. But could something horrible have gone wrong? I squirted oil in each spark plug hole before I started messing around in the hopes that that would lubricate the cylinders, but it was about 3 hours before I thought to check the compression. The engine never ran, so I never registered any oil pressure in all of my attempts (probably a dozen) to start the engine. Could I have damaged the rings or sleeves? In the absence of other ideas, I plan to pull the head and check into this timing issue sometime this weekend. But I sure would like to hear what you guys think.
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