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1973 Johnson 20 hp only starts once every few days

I

iafish

New member
I have a 20 hp Johnson seahorse, since i bought it a month ago it only wants to start like every other day. When it pops off i can keep it running as long as i keep giving it throttle. It will not stay running at idle. Once its dies it will not start again for atleast a day or two. Help please.
 
racerone said:
Do the basics on that motor.------Test the spark.--------Will it jump a gap of 1/4" or more?--------Yes or no?
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but if it was a spark problem why would it ever start? Also like i said what i think is odd is it will fire right up every other day but only once until shut off then wont run again for 2 days.
 
Why do you not want to answer a question.----------If you answer questions folks here can lead you to what you need to check next !!!!
 
You can buy an open air gap spark tester at most parts houses for around $8.00. Set it to 1/4" open air gap, put a plug wire on it and crank it over.
 
IF (and we don't know yet), but IF it has good spark, it may be getting way too much gas. That's called "flooding". That would account for the stalling, and for the two days thing. You let it sit for awhile and the gas drains off or evaporates---till next time.
 
kimcrwbr1 said:
Does the engine have good compression is the first thing you allways check. Do you know the history of the motor? If the compression is good replace the points and condensers, rebuild the carb and fuel pump. Replace all the fuel lines. Go through the lower unit check gearoil and replace the impeller. Do you want it to run or do you want it dependable. Get to know the motor now for trouble free operation out there on the water.
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Got it with boat that i bought from my brother inlaw who is a mechanic and crazy about keeping his stuff nice. Only thing is he hadnt used it much in last 2 years. I already replaced the impeller and gear oil is good. Not sure how it would get flooded tho. He said the carbs had been gone threw the last time he ran it.
 
How can it get flooded? Well a couple of ways are over-choking, leaking float valve, Mixture set too rich, ruptured fuel pump diaphragm. Oops, that's more than a couple, isn't it?

Where's your brother-in-law when you need him?
 
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