Oil on spark plugs normal?

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   I recently completed a tune up with new plugs, wires, rotor, cap and pertronix electronic ignition.  The engine is running better than it ever has but when I was checking plugs after about 2 hours of operation, I noticed that the plug in the port/ stern side was wet with motor oil.  The plug in the starboard/ bow side was dry. The oil level is dead on full while the boat is floating in the water.  Does this mean I have a ring going bad? Maybe valve cover is leaking down onto the spark plug?   Any tips would be appreciated.

starboard/ bow side (dry):

port/ stern side (wet)

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cspruill Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: October-29-2012 Location: Heber City, UT Status: Offline Points: 71	Post Options Post Reply Quote cspruill Report Post Thanks(0) Quote Reply Topic: Oil on spark plugs normal? Posted: June-14-2018 at 11:19am
	I recently completed a tune up with new plugs, wires, rotor, cap and pertronix electronic ignition. The engine is running better than it ever has but when I was checking plugs after about 2 hours of operation, I noticed that the plug in the port/ stern side was wet with motor oil. The plug in the starboard/ bow side was dry. The oil level is dead on full while the boat is floating in the water. Does this mean I have a ring going bad? Maybe valve cover is leaking down onto the spark plug? Any tips would be appreciated. starboard/ bow side (dry): port/ stern side (wet)
	1983 Ski Nautique 2001

GottaSki Members Profile Send Private Message Find Members Posts Add to Buddy List Grand Poobah Joined: April-21-2005 Location: NE CT Status: Offline Points: 3327	Post Options Post Reply Quote GottaSki Report Post Thanks(0) Quote Reply Posted: June-14-2018 at 11:36am
	Yes, i suspect modest amounts of oil weeping from valve cover gaskets can pool in the spark plug hole, thus your stern plug has a little oil on threads
	"There is nothing, absolutely nothing, half so much worthwhile as messing around with boats...simply messing." River Rat to Mole

cspruill Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: October-29-2012 Location: Heber City, UT Status: Offline Points: 71	Post Options Post Reply Quote cspruill Report Post Thanks(0) Quote Reply Posted: June-14-2018 at 11:59am
	Thanks so maybe just try replacing the valve cover gaskets then?
	1983 Ski Nautique 2001

SNobsessed Members Profile Send Private Message Find Members Posts Add to Buddy List Grand Poobah Joined: October-21-2007 Location: IA Status: Offline Points: 7102	Post Options Post Reply Quote SNobsessed Report Post Thanks(0) Quote Reply Posted: June-14-2018 at 8:07pm
	What engine/year do you have? I had to change vale stem seals due to similar plug fouling. They were definitely cracked. Mine were the posi-seal, not umbrella. They can be changed without removing head, The spring compressor was about $20. Feed rope into cyl to avoid dropping valve. PS - good time to refurbish exh manifolds since they will be off.
	“Beer is proof that God loves us and wants us to be happy.” Ben Franklin

cspruill Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: October-29-2012 Location: Heber City, UT Status: Offline Points: 71	Post Options Post Reply Quote cspruill Report Post Thanks(0) Quote Reply Posted: June-15-2018 at 1:45pm
	I have an 83SN with the 351w. Any special tools other than the valve spring compressor? So did you have more issues with the rear cylinders or is that just the way it happened on mine. The fronts are dry and the rears are wet. Thanks!
	1983 Ski Nautique 2001

SNobsessed Members Profile Send Private Message Find Members Posts Add to Buddy List Grand Poobah Joined: October-21-2007 Location: IA Status: Offline Points: 7102	Post Options Post Reply Quote SNobsessed Report Post Thanks(0) Quote Reply Posted: June-15-2018 at 3:00pm
	IIRC the worst on mine were middle cylinders, but all of the seals had cracks started. Getting exhaust manifolds off will be hardest part, esp if they have never been removed. You could need a dremel or even a welder if screws are rusted in. Other than that no tools out of the ordinary. I bet 83 used the old umbrella style, so do some research 1st. Another thought is to make sure oil drain holes in head are clear. If it isn't using much oil, it might be a good decision to just get a plug that can tolerate oil. Maybe not tear engine apart in middle of summer.
	“Beer is proof that God loves us and wants us to be happy.” Ben Franklin

cspruill Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: October-29-2012 Location: Heber City, UT Status: Offline Points: 71	Post Options Post Reply Quote cspruill Report Post Thanks(0) Quote Reply Posted: June-15-2018 at 4:53pm
	I like that strategy! The plugs that are in it are brand new and its running better than ever so I think I will let it ride through the Summer and revisit in the Fall. Thanks again!
	1983 Ski Nautique 2001

Oil on spark plugs normal?

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