repeatedly fouling plug

lparkerjr1944

Recruit
Joined
Nov 27, 2014
Messages
1
I have a 1996 evinrude 40H E40TLEUE The lower plug fouls out repeatedly I have checked that the fuel/oil mixture is correct and replaced the Plug several times. The gap is what is recommended. Carborators have been cleaned. Nothing worked so far the plug fouls whether I'm at an idle or running full out. Any suggestions?
 

GA_Boater

Honorary Moderator Emeritus
Joined
May 24, 2011
Messages
49,038
:welcome: aboard, lparker1944. Moved your thread to the Evinrude forum. You have a better chance for help here since it is something with the motor. Good luck.
 

Tim Frank

Vice Admiral
Joined
Jul 29, 2008
Messages
5,333
Three suggestions:

1) Buy an OEM manual; best investment you will make.
2) Read the Top Secret files at the top of this forum. There is a wealth of information and some great tips for effective troubleshooting.
3)
"and replaced the Plug several times"
In general, if you replace any part several times without getting any positive result, you are just guessing, and would be better to just open your wallet and your car window and throw the $$$$ out and get it over with.... :)
I know it is "only" spark plugs in this case, but that is still ~ $10- each time, and I'll bet that you've thrown out at least 4 perfectly good plugs.

Systematic troubleshooting will get you to the root cause of the problem and you'll know what really needs to be replaced....if anything.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,035
Check the pulse line on your fuel pump. If it has raw fuel in it, the fuel pump may be leaking fuel into the crankcase, fouling the spark plug.
 

WrenchHead

Petty Officer 2nd Class
Joined
Feb 15, 2009
Messages
120
You say the bottom plug fouls so that means you have at least one other plug. Therefore the problem is probably in the cylinder. Do you have only one carb? If so then it ain't the carb. As suggested do a compression test, you may have a bad piston ring. As another test, trade plug wires with the good plug and see if the problem moves. Leaking, or shorting out, plug wires will give you a weak spark and incomplete combustion.
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
What temperature is the motor coming up to when running ?? Especially at idle.
 
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