Hi I have recently been given this motor from a guy down the road. <br /><br />From what I can tell it seems to have overheated at some point since the gold around the top cyl is discolored and some of the plastic parts are melted a bit.. He said it was that was when he got it and it ran for years that way. Im not so sure but hey it was free.<br /><br />I started it up and it ran , but was leaking water around the water jacket. I took this off and replaced the head gasket and water jacket gasket. While I had it apart I inspected the Cly walls and they are in perfect shape as are the pistons. Once I put it together i did a compression check and the cyl are 110 105 110. Then decarbed and soaked in sea foam to clean it out a bit. I cleaned the carbs as they were all gummed up badly and started it up again.<br /><br />It ran smoother but will not run in gear under a load at all and will barely run in water at idle. It also seems to rev weakly. I suspected that it was not running on all 3 cyl. I tested all 3 plugs for fire, they are all firing well. ( I just checked visually) <br /><br />I then proceeded to isolate plugs and it seem the bottom cyl has no effect on the engine running, the middle cyl has little effect on the idle and the top cyl has a noticable performamce hit when removed. I can run it on any 2 and the engine will still run though although badly if the top is not hooked up so they must be trying. <br /><br />Any help on how to troubleshoot this engine a bit more precise.<br /><br />One more thing I would like to ask, does anyone know the proper way to disable the oil injection system on this motor at least for the time being. I am running premixed and want to continue to do so untill I can verify this thing is working. As it is I cnat keep it going long enough to test the oil injection.