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Big Fish Hunter247

1965 9 1/2 HP Johnson

9 posts in this topic

I was given a 1965 9 1/2 hp Johnson I was told if I could make it run I could have it my problem is I put a carb kit in it I can get it to idle but when I put it into gear and give it a little gas it dies? Im not sure whats goin on?

Big Fish Hunter247

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Did you clean the carbs when you put the kit in? It sounds like a stuck / plugged high speed jet to me, that or fuel delivery - fuel pump, hose, etc.

Is the primer bulb facing the correct direction?

marine_man

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Sounds simple but make sure that the vent on the gas can is open (if it has one).

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Yes I cleaned the whole carb there is a fuel pump on there I cleaned that too

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Yes I cleaned the whole carb there is a fuel pump on there I cleaned that too

Sure it's the fuel pump you cleaned? Sounds to me like you need to open your high speed screw a little at a time until she runs good. I know you said you put a carb kit in it, so I'm assuming this also meant a new needle and seat and if not start there.

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Is that a 2 hose gas line? If so make sure your gas cap is tight and there is pressure in the tank (push the little black button on top of the tank till she squeaks)

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Spark, fuel, and compression.

Did you remove the fixed high speed jet(not adjustable) and clean it or spray through it to verify that it was clean and free of crud? What happens if you try to richen the idle mixture needle. Do a compression check and verify spark on both cyls, just to eliminate other problems.

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What should the compression be for that motor? I know I have spark I put new points and condensers in it. I replaced the needle and seat so thats brand new. I tried turning the mixture screw I can get it to idle but thats all I tried it rich and I tried it lean I cant get it to go

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There is no spec on compression other than to have them fairly even. I have had some as low as 70 psi, be within 5 psi or so of each other, and have them run fine.

have you tried to choke it a little while trying to throttling up? I would still suspect the high speed jet in this case, but you need to eliminate spark and compression problems.

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