Oily residue on spark plug tip *updated*

BeaufortTJustice

Petty Officer 1st Class
Joined
Oct 8, 2009
Messages
248
Hey guys and girls,

While summerizing, I changed out the spark plugs on my 2007 VP 3.0 GLP-E engine. When I removed the two closest to the front of the engine, I noticed an oily residue on the tips. It was sort of brownish colored and looked/felt/smelled like engine oil. The residue was not there last year before winterization, nor did I notice it last spring when I changed the plugs (I briefly entertained the idea that it was fogging oil residue, but why only on 2 cylinders? and why not there after the previous fogging?). I'm sure this has been covered here before, but I could not locate a pertinent thread. I apologize if I missed it.

Background info: Boat specs are in my signature. I have owned it since 2009 and done my own meticulous maintence since then. I winterize before lay-up. My winterization routine is change engine oil/filter, change drive oil, drain raw water system and refill with non-toxic antifreeze, check plugs and wires, and fog engine. I always run Sta-bil in fuel and try to avoid ethanol. Boat is garage-kept when not in use.

I summerize by installing new plugs and impeller, and of course checking all fluids, hoses, belts.

According to my log, I have about 75 hours on the engine. Starts right up, runs smooth, even after any lay-up. Even with the residue on the plugs, it started right up several times on muffs after sitting for almost 4 months. No sign of water in the oil and doesn't seem to consume oil.

I did install new plugs and plan to check them for the same residue after I get a chance to run it in the driveway again, but in the meantime, I want to prepare a plan of attack in case the residue is still occurring.

Any help would be much appreciated. Thank you.
 

bnicov

Petty Officer 1st Class
Joined
May 25, 2009
Messages
348
Re: Oily residue on spark plug tip

Re: Oily residue on spark plug tip

See how the fresh plugs look after a few hours of running. It could just be some fogging oil residue that hasn't completely burned off yet. I wouldn't get too worried just yet. Keep an eye on them, we all should anyways, the plugs can tell you a lot about what is going on in the engine.
 

BeaufortTJustice

Petty Officer 1st Class
Joined
Oct 8, 2009
Messages
248
Re: Oily residue on spark plug tip

Re: Oily residue on spark plug tip

I plan on doing just that. TBH, I did panic a bit when I did a google search for "oil on sparkplug" and found lots of car people saying that it indicates worn piston rings or cracked blocks and all kinds of other major catastrophes. But to have worn rings and such after only 75hrs? I hope that is not a possiblity...

I am hoping for the best, but mentally preparing myself for the worst, if that makes any sense. Thanks for the reply, bnicov.
 

BeaufortTJustice

Petty Officer 1st Class
Joined
Oct 8, 2009
Messages
248
Re: Oily residue on spark plug tip *updated*

If anyone was curious on how this turned out...

I finally got a chance to hit the water and give the boat a good run. I checked the plugs after warm-up, and several more times over the course of about 2 hrs of running and found nothing unusual on the new plugs. I think I can breathe easier now.

Happy boating this season!
 
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