what caused fouled plugs.

[boat 1]

Hello,<br /><br />I have Merc 2002 9.9 HP 2 stroke. After I replaced the impeller, I am doing the normal routine starting, Now the motor easyly get fouled plugs.I have to change out plug to get it to start. But i stil have a hard time starting it.<br />when it started it will run great all the tim.<br />IS it feul problem or Carb problem ?<br /><br />Second, how many hours on motor do people rebuild the Carb?<br /><br />Third, If I have the floater in carb stuck on, Will that cause plugs fouled?<br /> any gugestions will be appreciated<br /> Thank you.

 

[andy6374]

Re: what caused fouled plugs.

You will flood your carbs if the float is stuck. If it is fouling the plugs so quickly, I would have to guess that your fuel/oil mixture is high.<br /><br />Do you run a premix? A 50:1 mixture is recommended.<br /><br />I would disassemble the carbs, clean'em, dry and blow out all orfices with compressed air, and reassemble with new gaskets every two seasons.<br /><br />I also use a can of seafoam 1-2 times a season.<br /><br />As far as not starting...Are the carbs getting flooded or do you have a weak spark?<br />-andy

 

[boat 1]

Re: what caused fouled plugs.

Hello,<br /><br />I am not sure if I have aweak spark. I normally take the top plug out and rest it agaist the block<br />I see the spark, but not taking the other one out.<br /><br />How do I kwon or what indications of weak spark?<br /><br />I've also been cleaning the Carb with seaform deep<br />creep 3 to 4 time per season.<br /><br /> Pls tell me more what to try or look for.<br /><br /> Thank you.

 

[andy6374]

Re: what caused fouled plugs.

Well Deep creep is good for maintaining clean carbs, but surely isn't a replacement for ripping the carbs off and doing a full cleaning like I described in my last post.<br /><br />To test the spark, get a spark gap measurer (any auto store), you should see at least a 7/16" gap.<br /><br />Do you have a manual for the engine?

 

[boat 1]

Re: what caused fouled plugs.

Hello.<br /><br /> I am sorry missae your question. Yes I run premixed 50:1.<br /><br />Yes, I have manual, facotry from Mercury.<br /><br />What's the next step Do i do?. If I disasembled the Carb, clean, saok and dry it. how do I maesure the floater in a Carb? I did rebuilt Carb once on 1980 Evenrude after that the moter runs fine. But it doas not idle. That before I get to kwon Iboat website. PLS tell me more. <br /><br /> Thank you.

 

[Vlad D Impeller]

Re: what caused fouled plugs.

Some motors suffer from constant fouling of the plugs due to having their T/stat stuck on open.

 

[WillyBWright]

Re: what caused fouled plugs.

Many 9.9s don't come with a thermostat. 15s do. If yours doesn't have one, it's not difficult to put one in.<br /><br />How are you using the motor? A lot of guys that use them solely for kickers mix at 100:1 to reduce fouling. That's only for motors that run at or near idle for long periods. You wouldn't want to do that if you run it fast.