How often should I change my plugs?

[ls1jay]

97 Pro V 150. Just got the boat and I looked at the plugs. They look pretty black. Engine seems to run good, but a little ruff at idle. Kinda sounds like it has a cam when I have it cranked and out of the water (with water muffs on of course). Will new plugs smooth out the idle or do they just idle a little ruff. It's not real ruff (doesn't sound like it wants to die or anything)?

[jb123]

do your motor a favor and clean your carbs, along with new plugs,check into a waterpump impeller change and lower unit gear oil change for peace of mind.i change my plugs about 2x a yr unless i have any issue or they rust. run "better" quality oil and use ringfree or equilavent frequently as a preventative.

[ls1jay]

Okay, when you say "clean the carbs" do mean with some type of spray carb cleaner, or something else like going into them? As far as oil goes I've been running the Yamalube and so did the previous owner. What's this ringfree stuff? Thanks for your help.

Jay

[Ken]

Jay - just spraying carb cleaner into the carb intake really won't do much. You can do a "shock" treatment with SeaFoam or RingFree and that might help clean them up. Also, you can pull the jets and squirt some Berryman's Chemtool into the orifices and that sometimes does some good.
Both RingFree and SeaFoam are strong detergents - when used in fuel they help to dissolve gum and varnish and loosen carbon buildup.
As far as when to change plugs - probably an average is once a year. Some owners do it twice a year, but that is for a lot of hrs use.
Good luck [img]smile.gif[/img] ,
Ken K

[ls1jay]

Ken,

Thanks for the info! I'm hoping this Yamaha will be a good motor. I've never owned one before, but I do know that when I go saltwater fishing with a friend, Yamaha seems to be about 98% of what's out there at Pine Island. I've owned a Chrystler before (total junk!), a Evinrude (not bad), a Johnson (seemed to have carb problems) and a Merc (great motor). Hopefully the Yamaha will be another great one.

Jay