1984 JOhnson 150VRO

nitrobill

Recruit
Joined
May 3, 2003
Messages
2
Recently had my 84 150 Johnson rebuilt after burning down and rejetted following the overhaul after it was lean popping at Idle. The dealer said he went 2 sizes on the mid and hi jets and 11 sizes on the Idle jets--now my motor has fouled three sets of NGK plugs and ran like crap when punched wide open until the engine was able to clear it's cylinders.(smoke and more smoke) the dealer installed Champions at $15/ plug(I had to pay of course) ---the motor still fowls the plugs and runs like crap after about three minutes of idling and yet the dealer won't rejet claiming--I'm not using johnson oil, not using premium gas--for the 6 years before that I never had any problems.<br /><br />I've tried the gas and oil change and it's the same thing--<br />Besides a new dealer can anybody suggest anything else?
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: 1984 JOhnson 150VRO

Wrong jets, Bill.<br /><br />Any TCW-3 oil is satisfactory and 87 octane fuel is recommended. Neither would cause fouling.<br /><br />Replacing plugs that only need cleaning and maybe regapping is another cash cow for dealers. Clean them and regap to .040.<br /><br />Your dealer is handing you lies to avoid correcting his error.<br /><br />Whose idea was changing the jets in the first place?<br /><br />Good luck. :)
 

nitrobill

Recruit
Joined
May 3, 2003
Messages
2
Re: 1984 JOhnson 150VRO

It was the dealers ---They "knew exactly what was wrong" and of course charged me about $490 to rejet--since then it's been back twice--each time it sits on his lot about 10 days until he can get to it--they're assholes--I've asked them to call me the day before they can work on it and I'll bring it in but they refuse to do that---so it sits until they can get to it--once they "decarbonized" it and replaced the plugs then did the same again and replaced them with this special champion plug that cost $15 per plug--they don't foul as often but hole shots are a smoking, dogged slow, mess unless I shut the motor down immeadiatly then start it and punch it immeadiatly--hard to do when your trying to water ski.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: 1984 JOhnson 150VRO

Stick with Champion plugs and 87 octane. There are several you can use but I have had good luck using (Q)L77JC4's. I would agree to richen up the mid and high speed jets if you insisted on using high test fuel and/or NGK plugs. Both create heat so a fatter mixture is needed to cool the combustion temps down.<br /><br />Its not unusual to rejet the idle for todays fuel but 11 sizes seems a bit intense.<br /><br />The most important thing is to determine why the motor had to be rebuilt and correct the cause. If the cause was not 100% determined it would stand to reason to jet up to hopefully prevent a repeat failure until the cause was found and corrected.<br /><br />You didnt mention the oil you are using but I would strongly recommend a premium brad oil.<br /><br />Good luck!
 
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