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Wow, I totally agree about the reed valves, (wasn’t going to push it :). Thanks for the carb info, and yes I’m still thinking something about the carb is to blame.
Fuel pump is pumping, getting fuel in the bowl now that I replaced the cork float which was cracked and not opening the float needle. The reason I asked about the reeds is because it acts like it’s not pulling fuel from the carb good enough to run on just gas. Yes, I have cleaned the carb (many times), new float, needle valve, needle seat, vent ports, gaskets…, new carb rebuild kit, (along with)… new coils, plugs, points & condensers. Spark tester shows nearly 3/8 ” spark jump. Compression is a little over 90 lbs, on both cylinders. Flywheel has good magnets, and the flywheel key is not sheared at all. Set the plugs to .035 and the points to .020 Using new gas with 50:1 oil mixture.
When my neighbor asked me to work on it, he said “it runs good, but was getting hot”. I removed the lower unit and turned the lower drive shaft using a battery drill with the water pump under water, and the water pressure seemed to be OK. So naturally, I changed the water pump impeller, and totally disassembled the entire block to clean all of the water passages in the head, intake and exhaust manifold. This is when I noticed two of the intake reed valves were not fully closed and were not aligned properly. Aligned the reeds and reassembled the engine. With all new gaskets (and thin film of REINZOSIL sealing compound) on the above parts, the engine does run on short burst of starting fluid, (and yes, I know starting fluid spray has no oil). It did try to run very shortly just one time on just gas, but I had it a full throttle and fully choked. I have tried every possible adjustment with the RICH/LEAN and IDLE on the carb. I just ordered an ultrasonic carb cleaning tank and cleaning fluid. Hope this fixes something I missed or just cannot see in the carb. Any advice is appreciated, and I’ll post if something changes. THANKS