Still having problems with my v-175 Mercury 2 stroke

So I have established i have a Frankenmotor.

Little back story. Bought the motor about 2 months ago that was sitting for about a year and a half. Boat was empty so nothing but fresh gas has been ran through it since I got it. I have had the boat/motor out a bunch of times now probably about 8hrs run time. New plugs, new spin on fuel filter, New primer bulb, new fuel lines going to the tank.

The good:
-Motor fires right up (cold or hot)
-Half throttle through Full throttle the Motor runs great!

The bad:
-At idle it has a miss (cold or hot)
-If you full throttle it from a stand still sometimes it takes off great and other times it suppers then takes off
-If you slow down from full throttle it usually stalls
-If you are at a steady rpm and hit a wave sometimes the motor will change tone/rpm

I did some research and found things like idle stabilizer (How can I tell if mine has been removed or not), bad switch box (any way to test that and where are they located on the motor?) also maybe a bad Stator (any way to test that)

If compression is good, I would start with a complete Tune up, carb clean, link and sync, rebuild the fuel pump and go from there.

Docksidemarineservices said:

If compression is good, I would start with a complete Tune up, carb clean, link and sync, rebuild the fuel pump and go from there.

Click to expand...

Thats another issue. I dont know the serial number so I cant order parts. I was going to change fuel pump but dont know which one to get. Could the fuel pump still be part of the problem even with the motor running perfect at wide open throttle, I figured if it was a bad fuel pump I would see a miss at high rpm not low rpm like im seeing

The stabilizer is that module above carbs...disconnect and chunk it. The tone changing when hitting wave is float levels off. Get a diaphragm kit for a 1986 150hp,clean carbs an check float level plus use new gaskets!!!