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JS 440 carb tuning?

5306 Views 3 Replies 2 Participants Last post by  OL JS Rider
I have a 86 js300 that i converted to a 440. I installed a bn44 mik and manifold on the engine. The ski starts easily but it is tempermental in all rpm ranges. the carb has a vac cap on the rev limiter port. I have been reading posts that talk about a restricter for removing the rev limiter. I have never heard of this. Any sugestions?
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If any one wants to run a 44 mm mic on there jet ski that didnt orig come with a rev limiter you must put a restriction in the return line. The rev limiter is a ristrictor it has a hole to pass fuel back to the tank that is appx .040 . I installed a restriction in my return line and now the thing runs great. I was pulling my hair out before i tried this.
I simply took a piece of 1/4 dia brake line about 4 in long and smashed it in the middle with the benchvice till it was difficult to blow thru but not too difficult. Then installed it in the return line.
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