Johnson 4.0 ID

Joined
Jun 3, 2004
Messages
21
Just picked up a 4 horse johnson and was woundering what year it is, fuel mix ect... <br />Serial # 4w75a<br />model # e4147920
 

rickdb1boat

Supreme Mariner
Joined
Jan 23, 2002
Messages
11,195
Re: Johnson 4.0 ID

1975. 50:1 mix. or about 2.5 ounces of TCW-3 oil per gallon of gas. 87 octane fuel
 
Joined
Jun 3, 2004
Messages
21
Re: Johnson 4.0 ID

Thanks Rick, I fired it up and it ran ok. Seems like there might be a fuel delivery problem, It want to idle up but only when i choke it. I'm thinking its in the mix to much oil. Would love to hear any ideas.
 

rickdb1boat

Supreme Mariner
Joined
Jan 23, 2002
Messages
11,195
Re: Johnson 4.0 ID

Try cleaning and rebuilding the carb with a carb kit. Should cure your problem. There are a couple of places online that have the kits or your local Johnson/Evinrude dealer will have it.. Do you know the history of the motor? Has it been sitting for a while? Last time the water pump was replaced? And if it has been sitting, a carb cleaning is for sure in order..
 
Joined
Jun 3, 2004
Messages
21
Re: Johnson 4.0 ID

My friend gave it to me and said it ran well except for the hesitation. The motor is real clean hell i'd eat off the carb it's so clean but if it sounds like the carb then so be it. How about the reed valves ? would they have anything to do with that ? Thanks again
 
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