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1977 DT4.5 power loss above 1/3 throttle
Hi,
I have a 1977/78 Suzuki DT4.5. It's been stored in my father's loft for 30yrs but has been dry, relatively warm and regularly turned over. It only had about 20hours use before being laid up, and we managed to get it started OK after a bit of a clean and flush through (result !). It works well enough (although a bit smokey) and I've been out and about using it in my sailing dinghy. I don't need great speed, just some extra oomph for when the wind/tide are not in my favour.
Problem - it will idle fine, and push the boat along as long as I don't turn the throttle beyond about 1/3 open. If I do, the power drops right off and the engine stalls. If I catch it doing this and close the throttle back down it recovers and will keep chugging along fine. There doesn't seem to be a problem with fuel flow as fuel will flow freely out of the drain tube when I press the black button on the carb. Spark plug has the correct gap and I've tried different slow/fast settings on the carb but with no joy. What could it be ? Would be nice to know I had the extra power if I needed it...
I have a 1977/78 Suzuki DT4.5. It's been stored in my father's loft for 30yrs but has been dry, relatively warm and regularly turned over. It only had about 20hours use before being laid up, and we managed to get it started OK after a bit of a clean and flush through (result !). It works well enough (although a bit smokey) and I've been out and about using it in my sailing dinghy. I don't need great speed, just some extra oomph for when the wind/tide are not in my favour.
Problem - it will idle fine, and push the boat along as long as I don't turn the throttle beyond about 1/3 open. If I do, the power drops right off and the engine stalls. If I catch it doing this and close the throttle back down it recovers and will keep chugging along fine. There doesn't seem to be a problem with fuel flow as fuel will flow freely out of the drain tube when I press the black button on the carb. Spark plug has the correct gap and I've tried different slow/fast settings on the carb but with no joy. What could it be ? Would be nice to know I had the extra power if I needed it...
HUMAN-BUILT = HUMAN-FIXED
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