These parts are from a Magnum Pro .45 engine. You might not see the defective spots on these parts, but an inverted torque roll caused the engine to strike the ground with alarming force. The carb lost the high speed needle, broke the carb mount in the front engine casting in several places, and the muffler decided to break off some of the exhaust port and mounting threads as it departed the engine. Normally, this would make the engine a good candidate for land fill fodder. We however, held onto the engine. Whilst cruising Ebay (one of the auction web sites), another engine, advertised for parts only, was seen for $5.00. The good parts would make one good engine, since the parts needed to fix the original engine were OK on the auction one. The auction was won and the two engines will be reassembled into one good one. As a plus, we will have several metric screws and spare parts left over. In this photo, you can see all of the major assemblies for this two stroke engine. Each engine was stored in a sealed "baggie" until the rebuild was started. All our stored engines are wrapped in a cotton cloth with some ATF (Automatic Transmission Fluid) and stored in baggies. The engines themselves are lubed up with ATF to help prevent rusting, etc. The first step was to strip down both engines and clean up the parts in the ultrasonic cleaner. This is one of the two engines completely disassembled. We will use Dextron Automatic Transmission fluid (makes good after run oil!) to keep the moving parts lubricated. Keeping everything clean is imperative! When in doubt, clean the part again. Find a place that doesn't mind getting a little oil on it. We assembled the engine on the baggies used to store the engines. . We used a propane torch to gently heat up the engine casing for removal and installation of the bearings. This works really well! Only brief heat is applied to the casing, causing it to expand, while the cooler bearings are removed. Once the case was thoroughly cleaned, the new lubricated bearings were installed . Do not use any more than a few seconds of heat and move the torch around, don't leave it in any one spot for very long. We used a pair of leather gloves and pliers to accomplish the bearing replacements. The piston is lubed and then carefully slipped into the liner. The hole in the piston skirt must be positioned away from exhaust port. The exhaust port is the one marked with the alignment notch (seen in the photo). The liner was lubed and slipped into the engine casing. An alignment notch in the liner must be positioned adjacent to the screw hole above the exhaust port. Once the bearings were in place, the crankshaft need to be carefully installed through the bearings. Being careful not to scrape the crank's threaded parts against the bearing, we slid the crankshaft into place and applied some extra transmission oil in the bearings and on the crankshaft drive pin. We seated the bearings by installing a propeller. Aligning the prop so it was at the 10:00 position is easy when the front casing is off! Just keep the crankshaft pin at the top and then position the prop. We checked the free play and runout of the crankshaft. They were within tolerances (great news!!). The crankshaft spins within the bearings with little effort. Any binding or bearing grinding feeling must be fixed now, before proceeding any further. The front end was then installed into the main casing. Take care to align the gasket and the push rod onto the crankshaft pin as you slide the two components together. All four screws were put in place loosly at first and then gradually tightened at 180 degrees apart. The engine was checked for smooth motion of the crank and piston in the liner as the tightening process proceeded. You will find that slight biasing of the front end, either counterclockwise or clockwise will result a smoother motion of the moving parts. We finished tightening the four screws. It is starting to look like an engine again. We added some ATF to the push rod and cylinder sleeve whit the engine is open. We installed the head next. Each of the bolts were tightened gradually and at 180 degrees from each other. This allows everything to be torqued evenly. The head assembly was checked for leaks by submersing the head partially in some water. Ay leaks here must be fixed now. We didn't detect any leaks in this assembly. The carb throat was installed onto the front casting using some clear RTV to make sure there were no air leaks. The remaining steps are add a muffler and spinner. We will run the engine on the PSP test stand. The newly assembled engine must be broken in just like a new one. As always use a good new glow plug when setting up a "new" engine and verify the high speed settings every time a change is made to the idle setting. Since this is an ABC engine, the engine must be allowed to come up to normal temperatures for proper breakin. Running the engine blubbering rich and cold will destroy the engine. So we will run this engine near peak RPM and squeeze the fuel line to allow the engine to lean out for short periods of time. If the engine stops, it will be allowed to cool down some before restarting. This process will be repeated with longer and longer run times until the engine can maintain a reasonable idle at around 2300 RPM or less and run a full tank of fuel without stopping. Then the low speed idle mixture will be set so that the engine will idle for at least a few minutes without quitting. Adjustments of the idle mixture screw will be made 1/8 a turn at a time until a stable idle can be maintained for a few minutes without the engine stopping. As mentioned before, the high speed mixture screw must be readjusted each time the idle mixture is adjusted. Have fun and fly safe! 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