3JH2 - 3JH3 series
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Yanmar Pleasure Boat Marine Engine Help
Propeller Selection - 6LPA-P series - ZF transmissions
*While ZF claim the reduction is the same in forward or reverse, the HSW630A1 2.04:1 ratio transmission, now the ZF63A, was 2.10:1 in lefthand rotation. This meant the propellers, on a twin engine craft, had to be different to load the engines equally. If the engines are not loaded equally the most loaded engine will be overloaded, use more fuel and wear out a lot faster than the other.