'03 Johnson 50 Fuel & Choke Problems

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SoulWinner

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Greetings,

I am trying to help my brother with his outboard motor. It's about an '03 model Johnson 50 2 stroke outboard. He bought it new and it has never run well. It's always been real hard to start and wanted to die when you put it in gear. Well, he pulled it over to my house so I could take a look at it. Here is what I found and what I've done so far:

First off I noticed the choke doesn't work. It's got the ignition switch that activates the choke when you push the key in. When I push the key nothing happens with the little solenoid and there is no sound or anything. I have no idea what is wrong or how to fix this, and you advice is needed.

Next is the fuel issue. I couldn't get it to pump up with the priming bulb so I replaced the bulb with a new one. When I did, all manner of black gelatinous crud was in the old one. So I blew out the line and replaced the fuel filter. But then when I pumped the bulb only a little fuel would flow into the new filter. What's weird is I could unplug the fuel connector where the line plugs into the motor and it would spray fuel everywhere, so I knew the bulb was building pressure, and only then would the level of fuel in the filter rise, just when I unplugged the line. I would pump up pressure and then unplug the line and simultaneously the fuel in the filter would increase and fuel would spray from where the plug connects to the motor. So I did this over and over until the filter was full and tried to start the motor but the starter just ran and ran and the motor never tried to start or sputter or anything. So I got my wife to turn the motor over with the key while I sprayed carb cleaner in the carbs. It would run as long as I sprayed carb cleaner, but only as long as I sprayed the carb cleaner; so obviously it's not getting fuel.

I don't know how the fuel pump works on this motor, but apparently it's DOA. Can anyone here tell me how to perform the proper trouble shooting to make sure the pump is dead, and then how to replace or rebuild it? And also how to test and repair the automatic choke? I sure would appreciate any helpful tips and advice you can offer. Thanks much in advance.

Best regards,
SW
 
S

SoulWinner

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Re: '03 Johnson 50 Fuel & Choke Problems

One thing I forgot to mention is that I checked the spark and it does have spark. The plugs were the original plugs, but the showed zero wear. The motor has really low hours on it. Anyway, they were Champion plugs and I like NGK, so I got some new NGK plugs and replaced the old Champions. That had no net affect on the situation since it's not getting any fuel. But at least I know it will have spark if can get the fuel problem sorted out.
 
tashasdaddy

tashasdaddy

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Re: '03 Johnson 50 Fuel & Choke Problems

1st you need to determine if it is the primer soleniod, wiring connection, or ignition switch which is bad. i have had 2 quit, dirty wiring contact at the primer, get a volt meter and test.

pull the rest of the fuel line and see if they are clear. USE premixed gas instead of carb cleaner, carb cleaner strips all the lubrication off the internals.

easiest test for the fuel pump is to disconnect a fuel line at the carbs, and see if it is pumping fuel.

the motor if stock, has an OMS Oil mixing system fuel pump. i do not find a rebuild kit for it. new pump is $355.00. i have several of these motors, that i use. when i've had problems i have eliminated the OMS pump, and gone with a premix pump.

i don't care which plugs you like. the motor was designed to run with Champion QL87YC plugs. there is a difference, NAPA auto parts even has a note on there computers about other brands causing misfire problems with Johnson/Evinrude motors. get the correct plugs back into it.

http://www.boatsetup.com/Spark Plug Chart 2007 BRP.pdf
 
5150abf

5150abf

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Re: '03 Johnson 50 Fuel & Choke Problems

It sounds like the fuel tank needs cleaned if you are pumping out black goo, there is a filter in the tank that may be plugged and the carb is almost certainly plugged up, the motor fires when you spray cleaner in, you have confimed gas is getting to the motor so the next step is a carb rebuild.

If the bulb was full of crap the old gas line is too so replace it and if you have a see thru fuel filter they will only fill all the way up with the bulb, as soon as you start the engine it will drain but the motor runs fine.

As TD said, carb cleaner cleans off all the oil on the engine internals so don't do that anymore,use a small squirt bottle or dental syringe with the right premix.

As to the choke, start at the solenoid and see if there is voltage, clean all connections well and assure a good ground and check all the fuses inside the engine, always do the free stuff first.

And a safety note, if you are spraying gas all over the boat I certainly hope you have fire extinguisher close by, it takes very little to ignite gas.

Check all that and repost, I owuld of coarse reccomend an OEM manual before tearing into the carbs.

Good luck.
 
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SoulWinner

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Re: '03 Johnson 50 Fuel & Choke Problems

Hey, thanks for the replies. I'm trying to get a hold of a service manual right now. I can't figure out how to get the VRO pump off of the back plate of the flame arrestor. It's held on with three rubber doodads that have me stumped. I wish they would just used bolts or some other regular mechanical fastener. I will get some champion plugs for it to; although this motor has been such a temperamental POS since it was new that I can't see how plugs could possibly make it any worse. Anyhow, thanks for the advice. I'll report back when I proceed into this project a bit more.
 
tashasdaddy

tashasdaddy

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S

SoulWinner

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Re: '03 Johnson 50 Fuel & Choke Problems

I had to take it to a pro to get it fixed. A I was getting into this thing deeper than I really wanted to go I decided to put it all back together and take to a guy who operates an outboard motor shop with an impeccable reputation. After several days he called me up and said he needed to rejet the carbs. the idle was set too low, and carbs were jetted improperly at the factory, running the motor too lean. He rebuilt both carbs, re-jetted them, did some other stuff. for the first time since this motor was purchased new in '02 it starts when you turn the key, and remains running when you shift it into gear. A miracle!!
While it hasn't restored our faith in OMC/Johnson/Bombardier, at least now my brother can go fishing without all the hassle of fighting with his outboard motor.

Thanks for all the replies!
 
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