1999 Johnson 130hp quit working?

[thyNemesis]

Good day,

I have been running all season without issues till a few weeks ago and now I find myself chasing an erratic problem which I will try and explain.

I completed a carb rebuild on all my carbs, been working fine for many months. Recently I am having some starting issues. I took off the cover and was looking at my carbs, they seem to be dripping fuel out the intermediate oriface. I had taken off the primer solenoid and tested it with +12 and it worked. I've taken apart the carbs again and checked for any kind of dirt or foreign particles and they look clean. I clean them again while they were apart again.

So, today my wife started the boat while I went and parked the truck. I came back and she said it was running for a few minutes and just now stopped working when I arrived. So I proceded to crank it over a few times with out hitting the primer, turned over but no starting. I pulled the cover and noticed the fuel dripping from the intermediate oriface.

Got back home, hooked up the ear muffs and tried starting it again, engine would not start. I tried cranking the engine over and it seemed like the starter would spin then dis-engage after just a second, even thought I still had the key engaged to crank. Is this normal?

While cranking I had exhaust smoke coming out the prop area, but not running. After a few more tries it backfired once and I gave up for the night.

The boat has been running great for the last 5-6 months. New plugs, thermostats, waterpump, carbs rebuilt, new fuel bulb all done prior to the season.

Could the fuel solenoid be the cause of the excessive fuel out the intermediate oriface? stuck open or intermittently now working???

I also have an in-line fuel filter, small glass filter that from time to time has a blue tint to it, Oil. My set up has a water seperator->fuel bulb (horizontal oriented) -> in-line glass filter -> engine.

Why would fuel/oil mixture be in the glass in-line filter? is my fuel pump diaphram leaking?

any ideas?

 

[daselbee]

Re: 1999 Johnson 130hp quit working?

I cannot put a real cause to your symptoms, sorry. It sounds like you have two things going on, to me. But I know those carbs very well, and I know the throttle body assembly they bolt to. If what you say is true, and that gasoline is flowing out the intermediate orifice, I cannot picture a natural failure that would cause this. I can picture man-made failures that would cause this, but not something that would be a normal, natural failure. Let me explain....the intermediate orifice that screws into the face of the carb, is an air bleed orifice. The air enters (is sucked in by engine vacuum) and travels thru that labyrinth passage on the sides of the black plastic carb body. The airflow thru that passage, specifically when the air travels at the bottom of that passage, sucks fuel UP from the brass tube that extends into the fuel bowl, and partially atomizes it. (If you have cleaned these carbs, you MUST know these parts that I am describing). The fuel air mix continues to be sucked thru, exits the black carb body, and enters the throttle body, and again it's path is accessible and visible if you take the throttle body side plate off. There are small holes that lead to the venturi bore. Here is the key point....how can that path be blocked on all four carbs that would allow raw fuel to overflow OUT the front of the carb from the intermediate orifice? I cannot see that happening. I have some questions: Are you sure the fuel is coming from the int. orifice, and not from some other part of the carb? If it is coming from the front, six o'clock position brass hole, then that's not the int. orifice. That's just a bowl vent, and I can definitely see how fuel could come from there. If so, check for float levels set too high on all four carbs. That's the man-made fault I was talking about. To specifically answer your question: NO, the primer system cannot cause fuel to leak out the int. orifice. But, depending on the tilt of the engine, excess fuel from the primer system can flow out the front of the carbs. It won't be much tho. Now on to the backfiring. To me, a backfire is a loud blast like a shotgun out the prop. Is that what you have? Whenever I hear the description "backfire", I immediately suspect timing shift first. I rule out the timing shift before looking at any other cause. It is the easiest thing to check, using a timing light, and the check is free. To do a minimal check, set up timing light for #1 cyl., crank engine and make sure the mark on the flywheel appears very near the timing pointer on the block. That is a gross check that will usually suffice. If it is way off, say 60, 90, degrees away from the timing pointer, something is very wrong, and must be corrected. Most probable causes of timing shift (in order) are: center magnet ring of the flywheel has moved, or the flywheel key has sheared, or a defective timerbase or power pack. I hope this helps you get started...I know it is much to consider.

 

[boobie]

Re: 1999 Johnson 130hp quit working?

Have you checked the spark with an open air gap spark tester set at 7/16" ??

 

[thyNemesis]

Re: 1999 Johnson 130hp quit working?

daselbee,

Thanks for explaining how all that works, very informative to say the least!

So, it looks as though I might have a few different problems at hand. I need to address each one in turn, I need to simplify my troubleshooting techniques.

Perhaps the fuel leakage is just another issue I need to resolve. I've included a picture of the openening that appears to be leaking. Not all 4 carbs are leaking, just the top two and 1 more than the other. The bottom two carbs I would say are just wet from the drippings from above. I will address the float bowl issues in the coming days once I get the engine to stay running.

I think I might of identified that openening incorrectly, It could very well be the "bowl vent" you described.

You wrote "that the tilt of the engine could cause excess fuel from the primer system to flow out the front of the carbs", I usally keep my engine tilted at a 45 degree while it sits in my drive-way. Is this not a good practice???

Yes, the engine did backfire once, loud shotgun like blast. It only happened once and has since ran for a few minutes without issues. I will borrow a timing light and check this.

Upon further investigation today I have other information to supply.

Purchased a spark tester, sort-of like a sparkplug you attach to the sparkplug wire to visually check for spark.
Engine cold, late evening so I could see the spark better, connected to cylinder #1, nice blue/white looking spark. Engine cranked over and ran somewhat ruff (one sparkplug wire disconnected), had wife shut it down and proceded to check all cylinders for spark. All looked like the first one. Cranked the engine over and ran for around 30 seconds and had the wife shut it down.

Waited a few minutes and tried to turn it over again, nothing. Started would engage and quickly dis-engage while the wife still had the key turned over. I had her try this a few more times and the started did the same thing. It dosen't seem like the starter is spinning the engine fast enough before it dis-engages. I decided to check the spark again and found 3 cylinders not sparking and 1 that was, however, it was not as bright as before. It seems as thought the spark is intermittent but I'm not sure since the starter is not turning the engine long enough to produce the spark.

I'm not sure if I am over-thinking and confusing myself.

So confused at the moment...

 

[thyNemesis]

Re: 1999 Johnson 130hp quit working?

forgot the picture.

 

[daselbee]

Re: 1999 Johnson 130hp quit working?

Yeah....you have timing issues. I personally think the center magnet ring on your flywheel has moved. It can go back to the correct position, and then run a bit and shift position again....causes erratic operation...sometimes OK, othertimes no start, backfires, etc. Also, the starter disengaging is an indication that it is trying to fire at the wrong time. To fix, you will need to pull the flywheel, look for witness marks or any other indication as to where that magnet ring was originally located. Mark it very well and very accurately, remove the old glue, and re-glue with JB Weld. Some ppl here will say it cannot be done, and granted, it is very difficult to set perfectly. A good witness mark will help you tremendously. If you can't re-glue it, you have to get a new flywheel. All of this is of course dependent on this diagnosis. It could be something else.......

And, the leak location IS NOT the intermediate orifice. That is a bowl vent. Intermediate (idle) orifice is on your pics at the 9 o'clock position of the carb face. I think simply lowering your float level a bit will resolve that. I am not referring to engine tilt while storing it. I am referring to any tilt UP when trying to start, as you press the key in. If the throats are angled down in front, some fuel MAY come out the front. Not likely, tho. Just a longshot.