Black Oil dripping ...

[krosemond]

from under the cowling and at the front of the prop of my '79 Johnson 150. I used a can of OMC "tune-up in a Can" while suffering through a bad gas situation in the keys sprayed into the carbs at fast idle. That is when it started. I just figured it was the "degunkification" of the product at work. But it has been a month and a half, 20 hours of run time later and it is still dripping, although it is not much, I do notice it on the driveway and the lower unit. I wiped it off before going to the lake on saturday, and by sunday it was back.<br /><br />Am I correct that it is still the solvent dripping out? Is there something else I should check?

 

[12Footer]

Re: Black Oil dripping ...

Let's assume that the decarb worked very well,and opened everything up (kinda like blowin it's nose). Now, that it's breathing good,it may be running too rich,kicking-out the unburnt fuel as a black goo.<br />Perhaps re-adjustment of the carbs will elliminate this.<br />Surely the cleaner is long gone.I smoke mine 2 times a year,and the effects clear up in about 20 minutes.<br />One question, Does the primer ball get firm?<br />If you pump it,and it stays mushy,look up at<br />the carb while squeezing it.If fuel leaks from the carbs, it's a gummed float valve needle.<br />I don't have much experiance with that engine,so this is just a hunch.<br /><br />------------------<br />the Early bird get's the worm...So, he don't have to stop for bait.

 

[Paddling]

Re: Black Oil dripping ...

Hi Krosemond, I recently had this same situation with my 1986 150 hp evinrude. I had run it in the yard a couple of times and had the oily residue draining down the lower unit from under the cowling. I figured something wasn't right and finally found that one cylinder was not firing at idle throttle. After changing a power pack the engine idled better(of course) and the draining residue stopped. I have reasoned that the residue is un burned fuel and oil that drains out of the cylinder and is not washed away with the cooling water after you shut down. Maybe someone else can confirm my reasoning. Hope this helps.

 

[krosemond]

Re: Black Oil dripping ...

Thanks Paddling, 12Footer,<br />Here is a question that comes to mind, do you think it was not firing at all, or just at idle, or is that just the speed you checked it? She seems to be running well, wouldn't it be obvious that you were hitting on 5 instead of 6 cylinders? Wouldn't it backfire? I think I am going to take 12Footer's advice and check the carb floats.<br /><br />Cheers

 

[Paddling]

Re: Black Oil dripping ...

Krosemond, I think my engine ran on all six under load and in the upper rpm range, and lost one cylinder below about 1200 revs, but I could only check the fire at idle. It was idling poorly but did not backfire at any time. The big six cylinder runs mean on 5 or 6 plugs.

The hole I shoot in my own theory is how does the fuel/oil get from inside the engine to outside the housing? At any rate, getting mine to run on all six all the time has stopped the oily drain. Lets hear from someone else who has experienced this?

 

[Retro]

Re: Black Oil dripping ...

I had a similiar problem the other day with my Yamaha. It was running pretty rough on the water, so I cleaned up the carburetors a little bit and adjust the air/fuel mixture, and she ran great. But I did notice the same residue. The motor runs great, now, though.

 

[krosemond]

Re: Black Oil dripping ...

Great question Paddling. I get the drip from the exhaust port by the prop, but I have no idea why it comes out under the cowling. I have looked closely at the bottom of the engine and there is no wet areas. Could there be a leaky seal or gasket in the exhaust at that juncture?

 

[krosemond]

Re: Black Oil dripping ...

This thread got me thinking, so I began to do some further diagnostics. Sure enough, one cylinder was not getting any spark. The plug was perfectly clean, not a trace of carbon. When tested, it would not spark. At idle, when I pulled the wire, there was no change in the way it ran. But at higher rpm's, the boat seemed to run fine. So i cleaned all the connections on the coil and got a spark with the plug out, but upon reinstallation, same situation. Pulled it out and no spark. I then cleaned all of the connections again, as well as the ones for the power pack. Put the plug back in, and got a good arc from the wire to the plug, and a slight change in idle when the wire was on/off. Pulling the wires off the other cylinders created a very noticeable change in idle. I did this in the driveway, so I could not test higher rpm's under load. Any ideas on what is happening? If I am getting a strong arc at the questionable plug, can I rule out a bad coil? There seemed to be compression with the informal finger test. I am just wondering why that now I am getting a good spark to that cylinder, when I plug the wire off, it doesn't effect the idle nearly as much as the other cylinders, although I did feel a change vs when there was no spark at all. I pulled the plug after running her in the yard for 10 minutes or so and there is evidence of combustion.<br /><br />Any idea what to do next? Or if she runs better at the lake, can I be satisfied with my efforts? Apparently, 5 out of 6 is enough to make this engine seem to be running normal.

 

[Paddling]

Re: Black Oil dripping ...

Krosemond, now you are right where I was when I found my prob, no spark at one cyl. If your problem is intermittent, you may not be able to find it until it fails for good, but you may be able to make it move and pin it down. First I cleaned all plugs keeping them in same cyl. I swapped two plug positions, no change. Next I swapped two plug wires, no change. Finally I swapped two coils, no change. The problem stayed right with the original cylinder, so the problem had to be upstream, in the power pack. My engine has two power packs so I swapped them. The problem moved so I shelled out some bucks for a new one. Now I have the same performance at all cylinders with a very noticeable drop when any plug wire is pulled. I have bought bad plugs, i.e. cracked ceramic, which short out rather than fire, and a bad plug wire will jump spark to ground which you can usually see in low light. Weak coils are harder to diagnose, cause their resistance is so low to start with and you can't tell if internal wiring is shorted between turns. Hope you find it cause it takes longer to get out of the hole with just five firing

 

[krosemond]

Re: Black Oil dripping ...

Paddling, sounds like these are very similar engines, both OMC and only 6 years apart.<br />Thanks for the support. How hard was it to switch packs? How expensive was the new power pack? That sounds like the next step.<br />To switch coils, do you have to push the pin out of the connector to the power pack? If so, how did you do it without breaking anything?<br /><br />Cheers

 

[Paddling]

Re: Black Oil dripping ...

I'm not familiar with your year. My engine has two power packs and 6 coils and all bolt onto block with two bolts each and have wiring with sealing rubber connectors. It's a swim in the pool to replace mine. Cost for my pack was 116 at a local marine dealer. I couldn't find my pack for any less on the net.

 

[krosemond]

Re: Black Oil dripping ...

Thanks Paddling. Sounds like an identical configuration. The connector from the PP is a 4 prong one, one for each coil and (I assume) a ground. I was wondering if you could just push the pin out of the connector on the coil you want to switch. Is that right? Does switching the PP's from one side to the other affect the firing sequence?

 

[Beernutz]

Re: Black Oil dripping ...

Krosemond, if it's black gook, it's "burnt" oil. Check the bolts that attach the powerhead to the lower unit adapter. These either loosen up, or the gasket crushes, resulting in leak. Sounds to me like the mixture you were burning with the bad gas and "tune-up in a can" could have caused detonation in the adapter, and may have blown out or weakened the gasket.

 

[suttonc]

Re: Black Oil dripping ...

What plugs should I be running with my 1989 225 Johnson? Thanks for the quick response! Also, JB, DHadley, and all the rest of you guys are great!