1999 Johnson 115 starts then dies

Last week I took my (new to me) boat out. I ran up the lake a few miles to my fishing spot. When I slowed down the motor died. I tried restarting it several times but it wouldn’t go. The motor would crank over, fire up then die within a second. I had starting issues while getting it ready for use and found my ignition switch was bad so that was replaced. After that it started just fine on muffs.
When I first put it in the lake it started and ran great then the above happened. The motor is a J115pleem non ficht.
Does this sound like a fuel issue or electrical? Pumping the bulb while trying to restart it didn’t help. It just kept dying out. I haven’t been able to try it since that happened as my starter is completely worn out and a new starter will be installed this week. VRO system is still functional with no plans to remove/bypass it. Spark plugs are new Champion QL78YC as recommended for this motor.

Start with the basics, compression and a spark gap tester

alldodge said:

Start with the basics, compression and a spark gap tester

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I’ll be heading home from the lake tomorrow to pick up the starter that arrived today. Once installed I’ll do a compression test and repeat the spark test I did 1 1/2 weeks ago. I’m hoping the issue is something simple.

Do the spark test when it dies out, you know it has spark at times or it wouldn't fire up. When it dies, is when you need to know if their is still spark. Same with squeezing the primer ball, do it when the motor starts to die out.

That motor should have the quickstart system. When it is cold started, the spark is advanced and the motor should run at about 1100 RPM until it warms up. When the motor is warm restarted, the quickstart system kicks in for 1 second or two. Have you tried advancing the throttle a bit when warm restarting? What is your idle speed, when she is running and warm?

A " new to you motor " ----Bad switch / bad starter is a sign.----Do a complete evaluation before you spend more $$$----Post actual compression values.----Running with tested VRO or 50:1 mix ?---Does spark jump a gap of 3/8" on all leads ?----Water pump impeller replaced ?----Overheat horn tested?

Your motor is acting just like mine did when the motor fuel pump failed. Try to squeeze the primer bulb rock hard. In 4 or less squeezes.

airshot said:

Do the spark test when it dies out, you know it has spark at times or it wouldn't fire up. When it dies, is when you need to know if their is still spark. Same with squeezing the primer ball, do it when the motor starts to die out.

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I had to replace the starter as the old one was so bad it wouldn’t even crank the motor over. Once I installed the new starter the motor fired up instantly. I ran the boat for about a half hour without any problems. I pulled into my dock and let it idle for a while then shut it down. I let it sit for about 10 minutes then tried restarting it. I got it to fire a couple times but it wouldn’t go. I advanced the throttle and it fired right up. I’m thinking after shutdown, fuel is somehow still getting into the engine causing flooding or I just haven’t figured out the proper starting method for this motor yet.

racerone said:

A " new to you motor " ----Bad switch / bad starter is a sign.----Do a complete evaluation before you spend more $$$----Post actual compression values.----Running with tested VRO or 50:1 mix ?---Does spark jump a gap of 3/8" on all leads ?----Water pump impeller replaced ?----Overheat horn tested?

Click to expand...

I have replace the switch as it was faulty. The starter was so worn it wouldn’t crank so I replaced it and the motor fired up right away. I have removed and cleaned the VRO oil tank, filled it with fresh oil and am running premix in the tank until I know for sure the VRO system is working. I have replaced the impeller but haven’t checked any associated alarms. The old starter was so bad that after a couple turns of the key it wouldn’t work. I remover the starter and took it apart. The bushing in the brush holder cap was worn in half, the armature was built up with metallic debris and the brushes were worn significantly.
I’m still figuring out the starting procedure for this motor as it seems every outboard is a little different and I need to adapt to them.

I checked the compression ant it’s between 115-120 on all 4 cylinders. Spark easily jumps a 7/16” gap. The fast start works and the idle drops after a few minutes on initial start up.
The problem I’m now having is when coming into the dock and I slow to idle speed I’m getting a lean sneeze that starts off slowly then gets bad enough the engine stalls and won’t stay running when I try restarting it which isn’t good when docking. I went down to the boat today and it fired up right away. It had been sitting for a few days and it only took one squeeze of the primer bulb before it was firm. I let it idle for around 20 minutes with the cowl off as I figured I would look for loose hoses/fuel leaks. I couldn’t find anything.
What I did find was the clear plastic roller cover on the throttle arm isn’t in good shape and I was able to lift it off easily as it wasn’t touching the timing cam (not sure if is supposed to be). I want to check the settings of the idle mixture screws but it looks like I need a special tool to make adjustments. Is it just a security torx bit that is needed? I also looked into the carb throats and the butterflies aren’t completely closed but it does idle at roughly 800 rpm in neutral, should the butterflies be fully closed and another adjustment made somewhere else to obtain proper idle? I downloaded what I was led to believe was a factory service manual but turned out to be a Seloc manual so using that is really hot and miss. I probably should do a link and sync but have no clue how to do that on this motor.
I’m not sure if any of the above would contribute to the lean sneeze or if I should just order rebuild kits for the carbs and do that. One thing I would like to know is, if I do rebuild them, is it safe to put the plastic carbs in an ultrasonic cleaner? I don’t have harsh cleaner in it, just a mixture of pinesol and water.

Throttle plates should be CLOSED at idle.-----Correct that FIRST and test run.------Replace that damaged roller.