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bellabeitz

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I don't know if i did this twice but here is my problem. 85 hp outboard merc 1976 I am having troublr with a couple of things, when I put it in gear it stalls out on me unless I am on full throttle imidiately, then it jumps and goes and I can throttle down to a slower speed. Second thing is after running full throttle for a short distance it will start to throttle down on its own, then I can prime the bulb on gas line and it will take right off again. I have checked connections on tank, fuel line and there isnt any leaks or anywhere it could be getting air frothanks
 
any idea where i can find a kit for a 1976 merc outboard model 850, i have tried two different tanks and two different lines so i dont think the problem is there
 
great thanks, could this fix the problem of stalling out on me when I put in gear, unless of course I quickly put it wide open then it will not stall.
 
That will fix the high speed operation for sure the diaphram is probably getting stiff The stalling when you shift is more than likely a slow needle adjustment but they both may be relevant.
http://www.marineengine.com/parts/m.../4366802-thru-4831998-usa/carburetor-assembly
The slow needles are #7 turn it in to lightly seated and back out 1 1/2 turns each. Allways adjust the slow needles in the water in forward gear after the engine is fully warmed up. turn the needle slowly in 1/8 turn at a time until the engine stumbles and back out for a smooth idle. wait five seconds between adjustments and do both carbs a couple three times for a nice smooth idle in gear tied to the dock at around 750 rpms.
 
bellabeitz said:
great thanks, could this fix the problem of stalling out on me when I put in gear, unless of course I quickly put it wide open then it will not stall.
Click to expand...

if the fuel pressure or fuel flow is low, yes it can cause both of the symptoms you are experiencing... in as much as you probably DO need a kit in the fuel pump after this many years, the problem could also be a deteriorated fuel line which is causing a restriction... this could be anywhere from the tank to the carbs...

when you pump the bulb it is increasing the flow and the pressure to the carbs, so it runs fine... until you stop assisting.
 
normally if it stalls when you shift into gear it is running too lean and could be several things or a combo of them all. Slow needle too lean, float bowl not at proper fuel level and vacuum leak. Those old carbs can have a vacuum leak in the throttle butterfly shaft if it has slop the carb needs replaced. The ears on the mounting flange can be bent from over tightening or reusing old carb gaskets. When you rebuild a carb lightly surface the flange on a glass table with 220 grit paper until it all shines the same and never overtighten the cab down. Good and snug is the technical term and allways use a new gasket when mounting a carb.
 
You can preadjust in the barrel but it is best on the water to final the adjustment after running WOT for a while to blow the cobwebs out then go back to slow and adjust it in forward gear on the water.
 
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