Crim,
I appears that you are going to find power valves tha are stuck in place. Here is a few tips that might help in your power valve surgery:
1. Once you have the cylinder off (with the head still attached), remover the plate and two bolts holding the exhaust ramp in place.
2. Remove the philips head screw that holds the rod in place, as well as the plug at the opposite end of the rod. Spray some type of lubricant (WD-40 or other) into the exhaust port, and onto/around/down beside every moving part of the power vavle. If it's really stuck, this will help you move things around. Don't be afraid to use plenty, as you will just wash it off later.
3. Using a pair of vise grips, clamp onto the idle gear (you have three shafts protruding from the bottom of the cylinder, and the idle gear is the middle one) and pull it out of the cylinder. Don't pry against the bottom of the cylinder, just pull straight up. You will need to use a fine file to clean the shaft later. Removal of the iddle gear will eliminate any issue with the correspoding drum vavle.
4. Grab the shaft on the drum vavle on the other side, and pull up about 3/4 inch, just enough to allow the activating rod to be removed.
5. Gently tap the end of the activating rod to get it to move out of position. If the lone drum vavle tries to turn, you don't have it up far enough, so pull up a little more. You might have to pull the other drum vavle up the same height to keep the exhaust ramp from binding, but this will become apparant during disassembly.
6. Once the activating rod is out, pull both drum valves out, walking the eshaust ramp out one side at a time (you will find later that the bottom of each drum valve is connected to the exhaust ramp, which is why you have to pull the drum vavles up together). I doubt you're going to be able to turn the valves until they are pulled out a little, so you will need to work with the exhaust ramp in the exhaust port to get it out. Once the drum valves are disconnected from the exhaust ramp, you can pull them all the way out, as well as the exhaust ramp.
7. Now comes the hard part, the cleanup of all of the power valve parts and holes. The parts: Try starting with some oven cleaner. If things are really crusty, this will not work, and you will need to head for the wire brush on the bench grinder. You'll just know when all of the carbon is gone. Make sure you wear safety glasses, as carbon is going to fly everywhere.
8. The holes: Well, this is a lot more trouble, as you will likely find a lot of crusty buildup in the drum holes. The best method is to use a dremel tool with the flexible extension and a wire brush bit. The flexible end allows you to get all the way to the bottom of the holes. However, if you don't have a dremel tool, you can use a large drill bit. Simply wrap 180 grit sandpaper, rough side out, around the bit using duct tape. You will have made a hone that you can use to clean the inside of the holes. Don't take off too much material. Also, either grind your drill bit flat on the end, or wrap some duct tape over the bottom so the bit can not drill into the cylinder. Either method will also work to clean up the other holes for the other parts. Clean everything with spray carb cleaner or parts washer, and IMMEDIATELY wash the cylinder with soap and water and then rinse with warm water. Blow off all the exess water with an air hose, including all the ports and hidden areas. Again, safety glasses.
9. Use a little two stroke oil to lube the drum valves during reassembly.
Good luck. If your power valve is really stuck, this is going to take quite some time, so be patient. Also, if you have a video camera, take some pictures of the cylinder, especially inside the exhaust port, before you begin. You can also set the camera up on a tripod on the bench to video the disassembly just in case. If you get stuck, check back with us at the forum. There are almost no problems we can't help get you through.
Rick
