1983 Johnson 15hp fuel problem?

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pjcalla

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First off, let me preface this post by saying this is my first outboard. I was drawn to the early 80's johnnyrudes since they seem pretty much bullet-proof and parts seem to be readily accessible. Another reason is that I "rented" a '79 15hp last summer and it pushed my (heavy at the time with wood decks) 1648 at ~19mph on the lake and that is good with me.

Anyway, last fall, I traded a spare trolling motor for the outboard, tank, new fuel line. The previous owner said he put in a new impeller, fuel pump, new prop, changed the lower unit oil, and put in a new carb kit. He said he ran it in a barrel to make sure everything was working as it should. I just got around to it last week, to get it ready for the lakes/rivers around me.

Last Sunday, I emptied the old gas out of the can, got fresh fuel, added oil 50:1 and some stabil marine to help with the ethanol. I got the motor on the stand, in the barrel, etc. I couldn't get it started. I pulled, pulled and pulled some more. I had primed the fuel, pulled the choke and put it in neutral/start on the tiller handle. So my attempt at troubleshooting began.

I pulled the plugs, they were wet, so I assumed I had good fuel supply, so then onto spark. I didn't have a tester at the time, so I did the whole put the plug on the motor and see if there was spark. There was, so my internet searching commenced. It was said that my plug testing was inadequate, so I went and purchased the actual tester along with a gap tool. Tuesday, I retested spark, and it was jumping a 0.50" gap with a blue spark and audible "pop". I then gapped my plugs at 0.30" and figured I was good, so out to the stand/barrel I went. Pull, pull, pull, no dice. WTF?

I looked everything over, pulled the plugs again and they were DRY. I looked over the whole fuel line, etc. and decided to pull the carb. The bowl was full of fuel and the inside was clean, which I assumed since the PO said he did the carb before he traded me. For shits and giggles, I took out the float, inspected the seat and needle (all good, obviously), and looked through the main jet. I sprayed some carb cleaner on it, and made sure I could see through it (I could before, but just for good measure). I did not take off the welch plug, since I don't have a kit handy. Anyway, after deciding the carb looked good, I put it all back together. Tried to start it again, but it won't start...and the plugs are still dry.

Last night, I decided to mess with it some more. I wanted to hear it run, so I sprayed some fuel/oil mix into the cylinders to see if it would run. Success! It started right up, I quickly shut her down since it was late and not in water. I honestly wasn't expecting it to run, but I'm happy it did, albeit brief. Today, I'm going to put it in my barrel and start it up again.

I guess, through all my ramblings, is what would cause my fuel not to get from the carb to the cylinder? The bowl is full, the carb is clean (at least the parts I got to). When I spray fuel into the cylinders to start, and get it started, will that cause the motor to start sucking fuel from the carb and eliminate my problem? Like I said, I'm a complete outboard newb. No, I haven't tested compression yet, but that is next on the list when I can borrow my FIL's tester.

Sorry for the long-winded post, I just wanted to provide as much detail as possible to troubleshoot my problem. Thanks in advance.
 
The only step that I can think of that you might have omitted would be to purge the fuel system of any old gas. If your friend that had the motor ran it last fall, that means it had fuel in the system since all the work was done on it. If the plugs were wet because of some old fuel, that may have been your only problem. Make sure you've got good fresh fuel in the carb and give it another try at starting. If you can get it started by squirting a little fuel mix in the carb throat, just do that a few times and that should have fresh fuel pulled up to the carb by then.

If it doesn't fill the carb bowl on it's own when you squirt fuel in it, you may have an air leak in the fuel system.
 
I put fuel down the throat, and she started right away. Let it run for 10 minutes or so, but couldnt idle down. The slowest I could go without it stopping was the "start" position. It looks like the roller stops opening the valve when I go past "start". It also looks like the black plate that the roller rides along is broken. I'll have to do some research to see.

At least it was running.
 
Well, after some research, it appears that my throttle plate is not broken. It looks like I need to perform the "link and sync" and adjust my low jet to get her running slower.
 

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