spark plugs

[grampa's toy]

I have a 84 150 vro the powerhead was changed to a 80 200 hp ,with the 150 intake and carbs.when I bought the boat it had nkg plugs with a center electrode. the mech put champion plugs with standard electrode. I am just learning outboards, the nkg plugs are eaiser to clean, but what is best for my motor?

 

[rickdb1boat]

Re: spark plugs

Use the same plugs you were using, but best to use the champion brand. They tend to do better in OMC products for some reason.<br /><br /> web page

 

[grampa's toy]

Re: spark plugs

rick thanks a lot. I hate to ask a lot of questions I know a lot about cars But very little about two strokes , even less about forums. but I'm amazed at the amount of people willing to help out.

 

[ezeke]

Re: spark plugs

My understanding is that Champion developed the "Q" series plugs for capacitor discharge systems. The "R" in some Champion plugs is for resistor, which type is known to cause misfire in CD systems. The "C" in the plug number indicates copper cladding to cut down on electrical interference, thus the J6J vs J6C, etc. <br />"Q" plugs are still a type of resistor plug, they are just designed to eliminate the problems of the "R" series.

 

[rickdb1boat]

Re: spark plugs

Here's a good article on Champion plugs and the meanings of the letters.<br /><br /> web page

 

[grampa's toy]

Re: spark plugs

thanks for the exellent web page.plugs I have don't that good after 40 mins. of running I will get some ql16v plugs. my boat has suffered years of neglect before I bought it, and I'm picking away at getting it running good. but the more I read these posts the bigger my list gets of things I need to check and the more questions I will need to ask.wish I had knowledge to share I know hydraulics and drag racing but have a long way to go on outboards

 

[rickdb1boat]

Re: spark plugs

I would give it a decarb also, as it may have some carbon built up in the cylinders. Read article below. Seafoam makes a product called "Deep Crank" that is sprayed into the carb throats with engine running at idle. You then spray it in each cylinder for a while until it dies and let it sit a while. When you fire it back up, it blows out all the old carbon build-up out the exhaust. Good practice to do every year. You can get Deep Crank at NAPA and other auto parts stores. Actually, any spray product that will decarbonize is fine. Seafoam is just the most well known. Replace spark plugs when you are done as they will be gunked up!<br /><br /> web page

 

[grampa's toy]

Re: spark plugs

rick thanks for the web site wish I found this forum before I spent 3000 dollars for a rebuilt powerhead. since carbon buildup and decarbonizing is is so important what is the best rpm for a long run 20 plus miles?