Home made throttle reversing system.
Greg, Several of us E31 owners have faced this same problem when repowering from the original Yanmar 2QM15 to the more modern Yanmar 2 or 3GM series engines in our boats. I have photos of two simple aluminum or steel brackets or straps one needs to make to convert the throttle arm to reverse operation that I'd be happy to send you back channel if you email me at
glynjudson@roadrunner.com. The principle is pretty straight forward, whereas the throttle cable now attaches to the arm, lets say at 2 o'clock, the arm you make is fastened over the original so as to change the cable attachment to 7 o'clock. Said another way, the arm you make should be twice as long as the original and be attached over it so it protrudes the same distance in the opposite direction over the pivot point of the arm (pretty easy to do). Now instead of pushing the old arm, you pull the new one, resulting in reverse throttle control operation at the helm. The other bracket is required because reversing the action of the throttle with that first bracket places the cable lower on the side of the engine as it approaches the new throttle arm. The second one lowers the outer clamp fitting on the engine equal to the amount you lowered the first one. A picture is worth a thousand words so let me send you the images and all will become clear. Do you have this problem as a result of repowering? If so, I'd be interested to know what the old engine was and what the new one is. Glyn Judson, E31 hull #55, Marina del Rey, CA
