Fouled Plugs = Carb Issue???

[Sfritr]

In my previous post about my engine dying (lost my MoJo )I took the boat home and decided to check and change the plugs. All six plugs were black and fouled. Can this be a direct cause or sign of carb issues?

The boat ran great all last summer and I never had a loss of power or sign of issue. Again, its a 96 Johnson 150.

Any thoughts would be appreciated.

[oteymc]

I'm no mechanic, but I had the same problem last year with my boat. I was told it was from idling too much and not getting a complete burn out of the cylinder (fished on a lot of idle only lakes). I know also that the fogging oil can foul the plugs the first time it is used after winterizing. I would think that if your Carb is causing the fuel to run to rich at times, it could cause the same scenario.

[Sfritr]

That would make sense. Most of the lakes I fish are idle only or are small enough that I don't need to plane out. Hopefully, this weekend I will take her out and see if the new plugs have corrected the issue

[oteymc]

I know I changed mine, and it was like I never had a problem. The tech told me to rev up the engine in neutral for 30 sec or so after idling around all day to keep it from happening again. Like I said, I'm no mechanic just telling you my experience.

[bilgerat]

The best thing you can do for any engine is to run it at full load for a while, preferably on your way in from a trip. This gets the cylinders (pistons and rings) at their hottest. This will clear out the carbon deposits from the tops of the pistons and the rings. Engines that never see full load die a slow death

[slonezp]

The best thing you can do for any engine is to run it at full load for a while, preferably on your way in from a trip. This gets the cylinders (pistons and rings) at their hottest. This will clear out the carbon deposits from the tops of the pistons and the rings. Engines that never see full load die a slow death

The speedo on my truck goes to 120mph but I've never had it over 90. Do you suggest I run it at full load?

I agree with everyone else. It's the idleing that is causing the issue.

[bilgerat]

The speedo on my truck goes to 120mph but I've never had it over 90. Do you suggest I run it at full load?

I agree with everyone else. It's the idleing that is causing the issue.

Full load and full speed are two different animals But you are right on about idling. It's the worst thing you can do to any engine (I'm talking prolonged idle)

[bass or bass ?]

A lot of the coves and the feed rivers on my regular lake are no wake zones. My motor hates running at no wake speed for very long. And when I get back on the main lake and open it up , it takes a while for it to build up speed and get on plane again.

[Sfritr]

I can't imagine that the gas, although treated with seafoam, sitting all winter didn't help the issue either. I can't wait to take it out this weekend and see if the plugs corrected the problem. BTW, since the switch to the new format I haven't seen a post anywhere from Catt or Way2Slow?? too busy fishing i guess.

[Wayne P.]

Keep your fuel treated with Sea Foam all the time.

[Sfritr]

Wayne

Seafoam goes into every engine I own, all year. I would buy it by the 50gal drum barrel if I could.

you can almost immediately tell the difference in an engine after running a tank of seafoam treated gas through.

[Triton21]

I can't imagine that the gas, although treated with seafoam, sitting all winter didn't help the issue either. I can't wait to take it out this weekend and see if the plugs corrected the problem. BTW, since the switch to the new format I haven't seen a post anywhere from Catt or Way2Slow?? too busy fishing i guess.

Catt is on Central Forrum every day.

Kelley

[BassThumb]

I can't imagine that the gas, although treated with seafoam, sitting all winter didn't help the issue either.

Have you tried Stabil in your gas over the winter? Was there any difference with the plugs afterwards.

I know that after I go through a long no-wake zone and then kick it down, the motor seems to sputter a little for a half second. What would be causing this? It feels like my plugs are too wet.

[Crestliner2008]

I always use Startron in my gas. Not only for the outboard, but the snowblower, lawnmower and sometimes in the car. Does a great job of keeping this garbage gas, shoved down our throats, at bay. Just took my lawnmower in for service and the mech asked me why I wansn't using the machine! I laughed as I mowed the lawn at least a couple of times a week last season.

Then I told him I use Startron and he said, "Ah...that's why!" End of discussion.

[scrutch]

I have a two stroke Merc.

Two stroke + prolonged idling = expensive death.

Seafoam will clean all that gunk out of your motor. Put an entire pint can into your tank (treats 8 - 25 gal).

Take that boat to a lake that you can make LONG RUNS and BLOW IT OUT!

Take some rags with you to clean all that gunk off your motor around the exhaust.

Your motor should run better.

[Sfritr]

Seafoam is always used in my engine year round. I treat the tank with every fill up. I have not tried StarTron. Actually, I have never seen it? Do you purchase it at a specialty autoparts store or is it carried in the big box locations?

Hopefully, I will be able to take the boat out this Wed., barring the rain that is forecast, and see if the new plugs have fixed the issue.

[junebugmn]

I have a two stroke Merc.

Two stroke + prolonged idling = expensive death.

Seafoam will clean all that gunk out of your motor. Put an entire pint can into your tank (treats 8 - 25 gal).

Take that boat to a lake that you can make LONG RUNS and BLOW IT OUT!

Take some rags with you to clean all that gunk off your motor around the exhaust.

Your motor should run better.

An old omc mechanic told me the 150's like to run full throttle, also has any one tried omc 2 plus 4? It cleaned up my old 150 also ran a can of omc engine tune to clean out the upper cylinder's but you have to follow the direction's on the can, it act's like a fogger but clean's out the carbon etc. Junebugman

[Way2slow]

No carb motor is going to do well with extended idling. DFI motors do a little better but carbed motors hate it. Four Strokes will do better but all two stroke motors a going to blacken the the plugs at idle. The motor needs a few minutes of WOT runs to help clean them. The only way you can check to see if you are really too rich is by doing a plug check. With the motor running at WOT for about five minutes, while holding it at full throttle, cut the switch off. Pull the cover off, trim it all the way up and take each plug out and check it. They should be a light to medium brown color, about the color of a paper bag. If the are Coke colored, that's not too bad but if they are still black, somethings wrong, it's too rich.

One word of caution, some boats that get up fully on the pad don't like this. They will show you what the term "Bat Turn" is all about. You will be too busy getting the brown out of you shorts rather than worrying about the color brown you plugs are. You can back of the gas and let the boat settle and then cut it off, just do this quickly. It's only take a few seconds of idle to start turning the plugs black.

Nope, I don't get on here very often now, don't care for the the new format. It feels like the forums have become a minor part of the page, the adds are primary. As I mentioned before, I know the bills have to be paid, but the site's focus seems to have changed.

[Triton21]

"Nope, I don't get on here very often now, don't care for the the new format. It feels like the forums have become a minor part of the page, the adds are primary. As I mentioned before, I know the bills have to be paid, but the site's focus seems to have changed."

Nope, same forum and people are the same just a new format that is paying for owner. IMO Good for Glenn and us as will let the forum pay it's own way. Get used to it.

Kelley

[Way2slow]

No, I don't have to "Get Used To It", all I have to do is not visit as much.

I know I can rub some the wrong way with my no BS attitude, but with my experience, I feel I have offered a lot good info to this site over the years. It's only the site that suffers when the experienced guys quit posting.

[Sfritr]

Way2Slow

I appreciate your opinion as you are entitled to it. And, I would like to thank you for your posts since I have been a member because you have saved me hours and hours as well as probaly hundreds of dollars in costly repair bills from your posts and insight. It is people like you, Catt, Jack (RIP), Glenn and the other long timers who "make" this site what it is.

I would hate to see any of the core members leave for any reason but I DO respect your opinions. You being on the forum is like Crash Davis (Kevin Kostener) in Bull Durham. Your great at hitting home runs and mentoring the young and impressionable fisherman here on the forum. Thanks

[Triton21]

Way2Slow

I appreciate your opinion as you are entitled to it. And, I would like to thank you for your posts since I have been a member because you have saved me hours and hours as well as probably hundreds of dollars in costly repair bills from your posts and insight. It is people like you, Catt, Jack (RIP), Glenn and the other long timers who "make" this site what it is.

I would hate to see any of the core members leave for any reason but I DO respect your opinions. You being on the forum is like Crash Davis (Kevin Costner) in Bull Durham. Your great at hitting home runs and mentoring the young and impressionable fisherman here on the forum. Thanks

I totally agree with 'Stritr'. Your posts have helped me tremendously over the years. I, and most of the other members here get tired of the whining and whining about something that is not going to change. I also will sorely miss your posts if you decided to leave. If I offended you I apologise.

Kelley

[Long Mike]

I'm a Startron fan. That stuff works wonders on fuel and carburators.