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post #1 of 4 (permalink) Old 02-04-2007, 03:34 PM Thread Starter
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Question fouled spark plug

my spark plugs are fouled ...does that mean i should get cold spark plugs or should i change the air to fuel ratio and if so how do i change it???
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post #2 of 4 (permalink) Old 02-04-2007, 08:35 PM
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you definitely dont want colder plugs and before I'd start messing around with heat ranges I would make sure the gas is fresh and your oil injection is properly adjusted along with your choke.sometimes this just happens the needle in the carb doesnt seat with the gas left on and the crankcase gets loaded up. verify the above items, there is an excelent link by SEG on the oil injection and you should be fine. you can look in your owners manual to make sure the right plug is installed too and as a general practice turn the choke off as soon as possible and limit idling as much as possible.
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post #3 of 4 (permalink) Old 02-04-2007, 09:06 PM
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You have to figure out where your problem is before you can fix it. Changing the heat range of the plugs will only mask the problem, not fix it. Check the main jets in the carbs and compare it to the factory specifications for your sled for temperature and elevation. Then check the oil pump to see if it is indexed correctly, as jearl suggested above.

If it's fouling at wide open because the fuel/air mixture is too rich, changing to a smaller main jet will help. If it's fouling when the power is in the midrange, you can lean out the midrange by changing the position of the e-clip on the jet needle by removing the needle and raising the e-clip (lowering the needle) one notch. If it's oil fouling, adjusting the pump like jearl suggested is the ticket.

If you do any jetting changes, make sure to pull the spark plugs and check them often. Lean is hot and hot will burn holes in the pistons! The plugs should be a cardboard brown when the jetting is spot on.

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post #4 of 4 (permalink) Old 02-04-2007, 09:12 PM
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Is it just one set of plugs that fouled, or does it keep doing it? If it's just the one set, replace them wit hthe same number. They foul sometimes, part of the game...

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