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1982 Johnson 70hp running rich

F

Frerman91

Member
I'm having issues with my motor running too rich. Would a float not seating
Properly cause this . (J70elcnb). Or is there something im overlooking.
I rebuilt all 3 carbs last fall and had problems getting one of them
Adjusted properly. This year it seems to idle rough and is fouling plugs.
 
There are no mixture adjusting screws shown on these carburetors.-----What trouble shooting have you done on this motor ?
 
Yes, I am aware there are no mixture adjustment screws I was referring to the float on the carb on the bottom cylinder I had fuel running out of the front of the carbs initially but got them fixed. When i went to start it the other day it flooded easily and the primer bulb doaent seem to get fully hard. Havent done much troubleshooting. Thats kinda what i was looking for info wise
 
Yes, I am aware there are no mixture adjustment screws I was referring to the float on the carb on the bottom cylinder I had fuel running out of the front of the carbs initially but got them fixed. When i went to start it the other day it flooded easily and the primer bulb doaent seem to get fully hard. Havent done much troubleshooting. Thats kinda what i was looking for info wise
 
I the primer bulb assembly, fittings and fuel pump were new last Oct, when I pulled the pugs when it flooded it wasn't just wet they were full of fuel, so I cleaned them, dried them and turned it over with the plugs removed and fuel sprayed your of the bottom cylinder I pt t he plugs in and it started but ran rough for a bit but cleared up some. I shut it down after 15 min and the plugs were black and wet.
 
Start with a compression test.----Post your numbers.-----Perhaps water leaking in from exhaust manifold gaskets.------
 
You have a leaking carburetor.-----Or a leaking diaphragm in fuel pump.----But perhaps it was water squirting out during cranking.-----Possible bad gaskets on exhaust manifold.
 
Is it possible the float in that cylinders carb has a float the is not closing, how can water get in that cylinder if it's holding compression.wouldn't all of them be affected if the fuel pump diafram was bad.
 
I bought 21 of these motors one time years ago.----I am quite familiar with them.----Fuel pump is driven by crankcase PRESSURE from one of them.---It has 3 separate crankcases.-----But good luck with yours.
 
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My apologies it wasn't my intention to irritate you or question your knowledge . I've owned several small outboard over the years without many issues I've had to do basic repairs on them but this one is new to me
I bought it with a 16' starcraft ss that had been sitting for 7 or 8 years. Surprisingly I was able to get it running fairly decent last year. after replacing plugs, wp impeller, fuel pump, fuel lines and rebuilt the carbs . It fished pretty good . This spring i completely gutted and rebuilt the entire boat . So i am now getting it running again after 10 months of sitting. So im questioning when I rebuilt the carbs I had issues with the float on one of them not closing when I set it even with the body so I'm wondering if it's sticking open
 
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