spark plug photo

[mikeyzx2]

Hey there ya'll! Been out running the "Big T" in Alabama, catching more UV rays than fish if you can imagine <br /><br />Here's a photo I took of the spark plugs from my Seahorse model J8RCOB. What is causing that black sooty ring on the porcelain? You can tell where the boots begin, only the exposed part has the black on it. It wiped off, but what would do that? I don't recall seeing that before. <br /><br />

 

[ezeke]

Re: spark plug photo

That is from the exhaust leaking around the threads on the spark plugs. <br /><br />There is a spark plug torque setting for your engine in the engine specifications section of your service manual. The setting is also specified in your owner's manual.<br /><br />Make sure the seats are clean and smooth on the cylinder head. You probably have some carbon built up there right now.

 

[mikeyzx2]

Re: spark plug photo

ezeke! that confirms my suspicions thanks! don't have the service manual for this motor, but OBJ told me 20 ft/lbs. sound about right? there was slight oil where the washers seat to the head, so I did suspect they weren't as tight as I thought. Thanks!

 

[ezeke]

Re: spark plug photo

Yes, it is probably 17.5 to 20.5 ft lbs, but I don't have the right manual for your motor. <br /><br />You can set those QL77JC4 plugs a little wider than .03 for trolling if you are fishing a lot. Don't go higher than .04 though.

 

[mikeyzx2]

Re: spark plug photo

yep, those are the plugs. I have a Clymer which is usually pretty generic but I'll take a look. Thanks again

 

[npd4432]

Re: spark plug photo

This is a rule of thumb for spark plug torque for a vehicle. With gasket on plug 1/4 turn after hand tight. W/O gasket 1/8 turn after. When in doubt use torque wrench to manufacture specs.

 

[mikeyzx2]

Re: spark plug photo

UPDATE:<br /><br />I hit the river today, and I think I may have found something........<br /><br />I noticed that when I would throttle up to WOT, it was slightly boggy then it would smooth out. And the idle tended to be a little rough and shaky. <br /><br />I popped the lid off while it was idling, and noticed some smoke coming out the back just below the head somewhere. Looks like a gasket leak, and when I open it up, it revs right up and I get moving up to speed pretty quick. And I notice it idles better. <br /><br />Is it a pretty easy job to remove the powerhead and replace the gasket? And does the leak cause a lean condition due to exhaust being recycled?

 

[JasonJ]

Re: spark plug photo

Yes, the leaky exhaust chokes off the engine, makes it run poorly. I'm in the same boat (so to speak), and had to do a ghetto repair after going through all the fuss of replacing the base gasket. I have posted my problem, and hopefully someone will have insight on how to fix it, as I have the same problem.

 

[mikeyzx2]

Re: spark plug photo

the only way to really fix it would be to change it, which is probably more difficult in a bigger motor. my local wrench buddy emailed me back and said we'd talk about it. he said it's not difficult. <br /><br />so what kind of ghetto repair did you try?

 

[seahorse5]

Re: spark plug photo

The black rings are soot particles attracted by the electrostatic charge on the sparkplug ceramic, not by exhaust gas leakage. If there were leakage, there would be streaked stains and no white areas right by the metal shell, where exhaust would have been leaking from.<br /><br />It works just like electrostatic air cleaning systems where the charge on metal plates attract the pollutants in the air.

 

[DJ]

Re: spark plug photo

Seahoese is correct.<br /><br />However, read the following topic.<br /><br /> http://forums.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=28;t=040811

 

[mikeyzx2]

Re: spark plug photo

Originally posted by seahorse:<br /> The black rings are soot particles attracted by the electrostatic charge on the sparkplug ceramic, not by exhaust gas leakage. If there were leakage, there would be streaked stains and no white areas right by the metal shell, where exhaust would have been leaking from.<br /><br />It works just like electrostatic air cleaning systems where the charge on metal plates attract the pollutants in the air.

Yep, it's attracting soot from exhaust leak under the hood. I reckon I'll fashion ram air on mine like JasonJ, but I'll bolt a big spoiler on the hood and somehow rig a "fast and furious" muffler to it, oh and maybe even some NOS!<br />

 

[JasonJ]

Re: spark plug photo

BTW, my plugs looked exactly like yours...<br /><br />Is your motor one of the low profiles? If it is, I recommend tearing it down and sealing the donut, don't do what I did. On the other hand, if you do choose to go the ghetto route, you can't just cut a hole above the carb and be done with it. That didn't help in my case, the carb was still low enough to suck exhaust gas. I had to take a plastic tube I had that was the appropriate diameter, and affix it to the carb top. I cut it flush with the hood so it would only draw fresh air, and put the Fast & Furious scoop on to keep rain water out. It works, but I am not happy with it, and will probably end up tearing the darn thing apart, again, and fixing it right.<br /><br />If it is not a low profile, you will have a much easier time fixing the exhaust leak, because the other motors would generally leak around the base gasket, and it is much easier to get the powerhead off.

 

[DJ]

Re: spark plug photo

Jason,<br /><br />"Punkinhead" is the one of the pet names for the 9 1/2 (Lo Pro).

 

[mikeyzx2]

Re: spark plug photo

I don't really like the looks of those old 9.5's they look bulky and they look like they don't have much room to tinker with the carb. <br /><br />My motor is not low-pro, it's standard issue design. The smoke seems to be coming out the very bottom, in the back by the hood latch. I can see it exactly but it's definitely not coming out the relief on the midsection and blowing back.