Re: difference between the two wire and three wire trim tilt motor?
3w motor has common ground plus two power leads. Motor spins in opposite directions depending upon whether green or blue gets positive juice. Black is always held to battery negative.
2w motor has just green and blue with no permanent ground. The motor spins in opposite directions by reversing polarity.
You can not easily swap motors. Each motor has a different mounting height relative to stern bracket studs and the oil tubes will not line up. The tubes are made from stainless and you are likely to strip your ports if you try to force them. that would be one of the worst things that you could possibly do.
you can directly wire the 2w pump by using a DPDT switch. They sell marine grade DPDT at my local hardware store for $6. You wire it to switch both positive and negative and to flip polarity from up to down. You'll need to run 2c-12awg from switch to motor. Your existing 3w switch is probably single-pole and won't work directly with 2w motor. You will need relays to use single pole switch. Relays go inside engine next to starter solenoid. They pull positive from starter and negative from engine block. You wire your old switch into them exactly the same way you wired it into your old trim motor. The relays will take care of everything and provide proper polarity swapping for 2w motor.
but it's all moot. you can't swap 2w for 3w without also swapping oil lines. Unless you are willing to remove system from boat then you're probably better off sticking with 3w.
