Top Spark Plug Fouling

[kreecher]

I have a 1995 60 HP Evinrude outboard (E60TLEOC)with 3 cyclinders that the top spark plug keeps fouling. The plug has heavy carbon build up on it. The engine will run but I have to replace the plug every few trips out and sometimes konks out at idle. I'm using the mfg recommended QL77JC4 Champion plugs, oil and standard 87 octane gas. I recently had to replace the powerpack which was performed by a dealer. Any suggestions?

 

[ob]

Re: Top Spark Plug Fouling

Don't know if it has anything to do with your problem but a 1995 60 hp 3 banger takes QL78YC Champions gapped at .030".The JC4's are optional ,but mine runs like a dog on them.The Yc's have a protruding nose electrode.<br /><br />If not ,I suspect that cylinder is running rich or has a weak spark issue.<br /><br />Have you run a compression test?

 

[Dhadley]

Re: Top Spark Plug Fouling

Welcome!<br /><br />Either plug should work fine if the motor is performing as it should. Did the top plug foul out before the pack was changed?

 

[reeldutch]

Re: Top Spark Plug Fouling

i would do a compresion test first then a decarb<br />and again do a compresion test.<br />are you mixing 50:1 After the decarb run it on a porteble tank for the next trip. premix 50:1 and disconect the VRO for that time.i use yamalube but there is plenty of other good oils.<br />so than you will know if there is something going on.<br />may be the top cylinder runs cooler than the other two.<br />but im not a mechanic.<br /><br />good luck reeldutch

 

[kreecher]

Re: Top Spark Plug Fouling

The motor ran like a champ before I took it to the dealer, no fouling on any plugs, but I knew the powerpack was bad before I took it to the dealer, the quick start wouldn't function properly. The dealer did reset the timing and adjusted the idle. I think I'm going to decarb and reset the mixture and see if that helps.

 

[Dhadley]

Re: Top Spark Plug Fouling

To be honest, if it didnt do that before he changed the pack I think I'd let him deal with it. If something happens you dont want to jepordize any warranty.

 

[kreecher]

Re: Top Spark Plug Fouling

I'm skeptical about taking it back to the same dealer. They're a certified Evinrude/Johnson dealer, but they replaced the spark plugs and couldn't even gap them correctly. One spark plug even had an electrode that was bent. I had to replace the spark plugs before the engine even started. Comment on the invoice was, "engine starts and runs fine". Thanks for the response.

 

[ob]

Re: Top Spark Plug Fouling

That bent sparkplug may be a clue to your problems.Was the bent plug strap on the top cylinder?Might want to remove the top plug and manually rotate engine until the top piston is near top dead and have a looksy with a pen light for excess carbon buildup on the piston head.That would be best case scenario.Unless the mechanic dropped the plug before installing ,you may have an interference issue.

 

[kreecher]

Re: Top Spark Plug Fouling

It's a bad coil, a $20 part. Decarbed and went with new QL78YC Champion plugs and she runs just great. Guys, thanks for all your help.

 

[ob]

Re: Top Spark Plug Fouling

Glad to hear you up and running kreecher and thanks for posting back with the update.