I broke one linkages changed it now it back fires threw the carb so hard it blows the fuel line off the fly wheel has timing marks you put it in the water and it bogs down and dies under a load

Put the engine in forward gear, in order to get WOT. Then, the bracket should hit the WOT stop bolt and you can check max timing. Also, you could compare the length of the new linkage to the old linkage and adjust, as necessary. That should set the timing pretty close. While you are at it, I would replace the spark plugs; examine the exhaust port for carbon build-up; and start using Amsoil Synthetic Outboard 2-Cycle Engine Oil, mixed 100:1. Too high of an oil/fuel ratio can cause big problems on 2-cycle engines and contribute to water pollution.