fouled plugs

[Duck Loads]

Good evening,<br /><br />The past 3-4 weekends I have been using my '89 Ranger 375v with Gt 150, 50:1 premix as a tube / ski boat. This past weekend the idle and slow speed operation was kind of rough. High speed was still OK. I pulled the plugs and all 6 were very black fouled. <br /><br />Would a couple of tanks (30-35 gall) of pulling at 2500 rpm foul the plugs, or is there some other problem that I might look for? Is there a way to prevent this?<br /><br />Thanks

 

[Dhadley]

Re: fouled plugs

What plugs do you have?

 

[Duck Loads]

Re: fouled plugs

QL77JC4<br /><br />Thans

 

[Dhadley]

Re: fouled plugs

Good choice. They may have fouled some but a high speed run should clear it out. 87 octane? What brand oil?

 

[Duck Loads]

Re: fouled plugs

Yes. I use 87 octane and John/Rude oil. After a high speed run things would smooth out a bit until I would put through the harbor to trailer my boat.<br /><br />Thanks

 

[Cricket Too]

Re: fouled plugs

Maybe your running rich and loading up on idle or slow speed.