Champion spark plug in Mercruiser

[texasvet54]

Attached is a picture of the Champion spark plug that I pulled from my Mercruiser V8. The Mercury shop said that I'm running a little rich and that is why it is all carboned up. How do I correct this and what does it say about the rest of my engine?

thanks,
texasvet

 

[Struc]

Re: Champion spark plug in Mercruiser

Do you idle and put around a lot? That'll do that.

Otherwise, you're probably in for a card adjustment / rebuild.

 

[mark1905]

Re: Champion spark plug in Mercruiser

That's an NGK plug, not a Champion. It says that your ignition system needs a tuneup, for one.

 

[Don S]

Re: Champion spark plug in Mercruiser

Doesn't say anything about the ignition system, says it's running rich and you should adjust your idle mixture screws to get best idle rpm without loading up. To lean you will have hesitation problems.
Is the choke all the way off?

 

[achris]

Re: Champion spark plug in Mercruiser

Don't ever, ever, ever, ever, ever, EVER use champion spark plugs in Mercruiser engines..... Unless you want constant problems.... Stick with NGK or AC-Delco....

 

[texasvet54]

Re: Champion spark plug in Mercruiser

That's an NGK plug, not a Champion. It says that your ignition system needs a tuneup, for one.

You are right. The other 7 plugs were champions. Why the last owner had one NGK, I dunno.

Texasvet