what should the rpm at idle be, my boat has a tach so I can set it right
R Rodnanaimobc Cadet Joined Nov 9, 2011 Messages 8 Nov 11, 2011 #1 what should the rpm at idle be, my boat has a tach so I can set it right
Joe Reeves Supreme Mariner Joined Feb 24, 2002 Messages 13,262 Nov 12, 2011 #2 Re: 1990 johnson 120 hp On a flushette, a 20" shaft model should be set to 1000 rpm, a 25" shaft to 1200 rpm. When put into the water the exhaust back pressure will cause the idle rpm to drop to normal.
Re: 1990 johnson 120 hp On a flushette, a 20" shaft model should be set to 1000 rpm, a 25" shaft to 1200 rpm. When put into the water the exhaust back pressure will cause the idle rpm to drop to normal.
