I purchased a Tower Pro .75 at a swap meet a couple of years ago. I added after run oil and put it in a bag. A few days ago I got it out and put it in a Tiger 60 (The OS 61fx was really tired). I moved the needlevalve to the carb (It was rear mounted). I went to the field to test run. The first few flips and it sounded flooded and then I started getting fuel spitting from the carb and possbly leaking from the front bearings. I disconnected all the hoses (air pressure and fuel) and the engine started and sputtered for a very long time without stopping. With additional expirementation I found that having the airpressure line connected was causing fuel to squirt out of the fuel line every prop flip and flooding the engine. I tried starting the engine with the air pressure line disconnected and was able to get it to run (roughly) for about 1-2 minutes. When I then connected the air pressure line as it was running fuel sputtered out of the carb and the engine quit. Any ideas? Questions? I am trying to figure out if this engine is damaged or can I fix it. I have 2 OS 61fx carbs and needlevalves but don't yet know if they will fit.