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Re: Full throttle needed to start Yanmar 2GM20F
If your engine was built after 1997 that might explain the difference. My manual covers the 1, 2 & 3GM models.
Normal start positing is at medium speed.
The exception is starting in cold weather the throttle should be in high speed with the decompression handle in the decompression position, start cranking and push the lever to the compression position, after it starts pull back to medium speed. There seems to be a conflict because there is a "caution" which states to pull back to idle immediately when the engine is started at high speed. We all know you should not rev a cold engine any more than necessary . The injection timing being delayed at high speed is also there.
I would actually be happy if the engine started right away on a 80 degree day, and came right back to idle without stalling.
Two things are happening when the decompression levers are placed in the decompression position..one..when the engine is turning over you are lubing the engine parts. Second..provided you are at the same time holding in the 'kill' or fuel cut off lever..thus clearing out any fuel in the pre combustion chambers and cylinders.
Once those procedures are accomplished while the engine is still turning over via the starter..release the decompression levers and the fuel cut off lever...