88 Johnson 25-35 conversion problems, help needed please

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Bowhunter1661

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Interesting bit of events. I purchased what I believe to be a 1984-87 35 carb off of a boat salvage yard. The carb didn't come with a float bowl so I went ahead and swapped my 25 hp carb bowl to the 35. Also rebuilt the carb completely (used every part in the kit). Motor also has new water pump, thermostat, plugs, wires, fuel pump, primer pump, fuel tank and lines.

When I swapped the bowl I also installed a new 35 hp jet, I believe it was a #65? The motor before ran like a top. Never skipped a beat. Now it sneezes at low speed (when cold and when coming down from high Rpms) and also is overheating badly. I ran it once, 1/4 mile from the launch and back. Checked the cyl head and I couldn't hardly touch it. I did this because I wanted to ensure it wasn't running lean at full throttle. Which it appears to be.

Before the Motor ran 30 mph at 5450 Rpms, with the 35 it ran 31 with 5650 Rpms. The carb was doing its job, just had tons of slip. Probably due to my beat up prop....

Idk, kinda lost. I pulled the 35 carb off and reinstalled my 25 just to be safe. It never use to overheat.

When at full throttle it runs like a raped date. Just not sure about the sneezing and high temps.
 
Well I took the boat out this afternoon after swapping the 25 carb back on. I can say it is going to stay on. The motor runs extremely well stock. Clocked it at 32 mph with the current and 31 against. Cannot really complain about that, especially on a 14 footer.. So if anyone wants a 35 carb upper, I have one for sale!
 
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