[DG] [DG] Rotary Drive selection

[Hg1]

I have a defective type 1 rotary drive unit, and have some questions on proper replacement. Sailboat is 40', 22,000 lbs. Existing rotary drive is type 1. All new Raymarine electronics a few years ago, including ACU 200, EV1, driving an older Autohelm Type 1. Drive has maybe 10,000 miles on it. On recent trip back from Bermuda, while sailing on a constant heading with wheel nearly neutral, motor started singing, and wheel locked up. Uppon return home, found that the sun gear is worn to a nub. All the planet gears are fine. Looks like it simply wore out. We sail offshore a lot in heavy seas, so the unit gets a work-out. It's been suggested that I go to a Type 2, but I have some reservations. The old Autohelm type 1 and 2 ran at different speeds (18rpm and 28 rpm). The new Raymarine units operate at 33 rpm for either type. I need gears that will last. Are the gears the same on both a type 1 and a type 2? Can an ACU200 be converted to an ACU400? I'm on the break-point in displacement. Current stop to stop is 1 3/4 turns. chain ratio is 3 to 1. I can go 4:1. How do you reconcile desired 10 second hard over to hard over times in your manual, when the Type 1 and type both run at 33 rpm, but you show different chain ratios for each?