My Johnson Won't Take Gas.... Seriously folks...

jcdargas

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Sep 9, 2003
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I was having MAJOR problems with my '99 Johnson 90 with the charging system. I got it repaired and finally got back out on the lake today. The problem is, the motor idles OK.... for about thirty seconds at 1100-1200 RPM and then dies. It takes several times to get it cranked and when I do, it refuses to take gas and dies. I have to crank and jam the stick forward several times before it takes enough gas to get going. Once it gets going at full throttle it sounds and acts great. Just can't troll at anything between 1000 and 2500 RPM without it's crapping out on me.<br /><br />This thing sat up for about three months before I was able to get it repaired for the electrical problem. I was told that the carb was full of oil from the oil reservoir when they went in to fix the charging problem.<br /><br />It idles great on the trailer hooked up to the hose but refuses to do what it's supposed to do on the water.<br /><br />Is there anything I can check/do to make this thing do what it is supposed to? Today just made the saying "a bad day fishing is better than the best day working" no so true.... I fish for stripers on Kerr Lake in NC all year long and I've been pretty much going nutz while the boat has been down. I need some real help.... quickly!!!<br /><br />Thanks
 

BF

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Re: My Johnson Won't Take Gas.... Seriously folks...

sounds like a gummed up carb (low speed/idle circuit) to me. Did the wrench disassemble/clean the carb that was full of oil, or just dump out the bowl?<br /><br />I dunno these motors in particular (just a hobby for me), so I dunno how a carb would get filled with oil (?).<br /><br />If you knew which carb was the one that had the oil, I'd bet a $1 that's where the problem is. Because of clogged/partially clogged low speed jet/orifice, it's probably not running on all cylinders, and falls on it's face when there's exhaust backpressure & load. If you bump the choke/primer when it stumbles, does that help? If it's not idling on all cylinders, it's not uncommon that it's not obvious on the hose (no exhaust backpressure or load).<br /><br />anyhow, that's my guess. Good luck.
 

jcdargas

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Re: My Johnson Won't Take Gas.... Seriously folks...

Originally posted by BF:<br /> sounds like a gummed up carb (low speed/idle circuit) to me. Did the wrench disassemble/clean the carb that was full of oil, or just dump out the bowl?<br /><br />I dunno these motors in particular (just a hobby for me), so I dunno how a carb would get filled with oil (?).<br /><br />If you knew which carb was the one that had the oil, I'd bet a $1 that's where the problem is. Because of clogged/partially clogged low speed jet/orifice, it's probably not running on all cylinders, and falls on it's face when there's exhaust backpressure & load. If you bump the choke/primer when it stumbles, does that help? If it's not idling on all cylinders, it's not uncommon that it's not obvious on the hose (no exhaust backpressure or load).<br /><br />anyhow, that's my guess. Good luck.
 

jcdargas

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Re: My Johnson Won't Take Gas.... Seriously folks...

Originally posted by BF:<br /> sounds like a gummed up carb (low speed/idle circuit) to me. Did the wrench disassemble/clean the carb that was full of oil, or just dump out the bowl?<br /><br />I dunno these motors in particular (just a hobby for me), so I dunno how a carb would get filled with oil (?).<br /><br />If you knew which carb was the one that had the oil, I'd bet a $1 that's where the problem is. Because of clogged/partially clogged low speed jet/orifice, it's probably not running on all cylinders, and falls on it's face when there's exhaust backpressure & load. If you bump the choke/primer when it stumbles, does that help? If it's not idling on all cylinders, it's not uncommon that it's not obvious on the hose (no exhaust backpressure or load).<br /><br />anyhow, that's my guess. Good luck.
 

jcdargas

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Re: My Johnson Won't Take Gas.... Seriously folks...

Sounds logical to me. They didn't "do" anything when they found the carb full of oil. Just burned it out.... This is a pontoon boat and the oil reservoir is mounted on top of the 24 gallon fuel tank, about two feet above the level of the motor.... My maintenance guy is going to move the reservoir over to the side that doesn't have the tank and mount it below the level of the motor to eliminate the "siphon" effect when the boat is not in use...<br /><br />Got any ideas as to what would clean the carb without removing it? Think a "carb cleaner" spray would do it?
 

jcdargas

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Re: My Johnson Won't Take Gas.... Seriously folks...

BF, I forgot to add, yes, choking it helps but it doesn't solve the problem. As soon as I release the choke it dies.....
 

Solittle

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Re: My Johnson Won't Take Gas.... Seriously folks...

jc - BF has it nailed - go for it.
 

jcdargas

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Re: My Johnson Won't Take Gas.... Seriously folks...

BF & SoLittle,<br /><br />Thanks for your input. I have a can of Mercury's "tune up" that I have never used. I'll try that to see if it blows tha jets open. If it doesn't do the job I'll look at removing the carbs and going at it the hard way...<br /><br />Thanks loads...
 

jcdargas

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Re: My Johnson Won't Take Gas.... Seriously folks...

BF & SoLittle,<br /><br />Thanks for your input. I have a can of Mercury's "tune up" that I have never used. I'll try that to see if it blows tha jets open. If it doesn't do the job I'll look at removing the carbs and going at it the hard way...<br /><br />Thanks loads...
 

jcdargas

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Re: My Johnson Won't Take Gas.... Seriously folks...

SoLittle,<br /><br />Not real sure that my last posted. Congrats on missing Ivan. Sure glad he turned west. Have two daughters in Orlando I was worried about... Breathing easier now.
 

BF

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Re: My Johnson Won't Take Gas.... Seriously folks...

Hiya,<br /><br />I'm not familiar with the Merc "tune up" stuff... If it is an aerosol that you're suppossed to spray into the carb throat, I pretty sure it won't work to fix the problem. It's probably more of a decarbonizing treatment (like "deep creep"), which is great, but that stuff follows the flow of air through the carbs, not the flow of fuel.... <br /><br />Mixing up a can of seafoam (available at NAPA) in a couple gallons of gas (or gas/oil if you premix) and running that through MIGHT work (worth a try). But there probabaly has to be some flow through the low speed circuit already in order for the stuff to flow through and get the cleaning done. Give it a shot, but don't be surprised if you really need to pull the carb and disassemble it a bit to clean it. While it's apart, then you can use aerosol carb cleaner to shoot through all the fuel passages (both forwards and backwards).<br /><br />Don't be alarmed by the amount of white smoke that pours out as you run the stuff through... seafoam in gas at a relatively high concentration like this is suggested by some on here as their favorite decarbonizing method... I like that it cleans the fuel side of the carbs.<br /><br />The choke info is helpful... confirms we're barkin' up the right tree (running too lean).<br /><br />Hope that helps!<br /><br />Brent
 

fireman57

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Aug 24, 2004
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Re: My Johnson Won't Take Gas.... Seriously folks...

Take seven minutes and check the diaphragm in your fuel pump. Mine had a small tear in it and had the exact same symptoms as yours.
 

jcdargas

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Re: My Johnson Won't Take Gas.... Seriously folks...

Gentlemen,<br /><br />I really appreciate everyone's input. Sorry for the time it's taken me to get back with my response but I've been up to my keester in alligators and this is my first opportunity to ge back with you guys.<br /><br />I am going to print up the responses and start from the top and see what happens. I wonder what the NAPA guys are going to say when I go in and ask for SEAFOAM. They know me and will probably get a good chuckle before giving it to me. I have oil injection and a 24 gallon tank.... Think I should add it to the whole tank? I have nowhere to put everything over 2 gallons....<br /><br />If all else fails I'll dive into the carbs....<br /><br />Thanks, again
 
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