Spark Plug Changes... a reoccuring theme.

[Wet-N-Frugal]

The majority of the time (NOT IN ALL CASES) unless your engine is missing or running rough, changing the plugs is overrated. The superior materials, superior manufacturing processes, AND ELECTRONIC IGNITION, make today's spark plugs last a long, long time.

My X22 has ten years and 800+ plus hours. Engine has always run strong and peppy. The plugs were changed for the first time two weeks ago; I know because we broke the factory paint on the 'spark-plug-socket cap' retainer bolts. Frankly I only changed them, well because, it had been ten years. And was not surprised to find most of them with good color, with little material loss, and not choked with carbon.

If quality, factory spec'd plugs are used, I would bet that half the time when new plugs fix a problem, it was because a plug(s) was not properly seated, and the change overshadowed the real issue.

Just my 1.9 cents.

-WNF

[epicfire]

I tend to believe you. I was thinking about changing mine because it seems to be the miracle cure to what ails our boats. Not that mine is ailing. I just do the routine maintenance with Mobil 1 products, keep the air filter screen/MAF sensor clean and it runs beautifully.

[FreeLance]

WNF - What do you mean by the plugs are not properly seated and how does this cause the fouling of the plugs and the boat to run rough?

Just asking because mine is running really rough and i am going with change the plugs to solve the problem!

[ktdust]

To seat them properly you have to torque the plugs to spec.

[blindside]

I've been forced to replace mine 2x due to 1 or more going bad after sitting in the winter. Probably since I do not fog the cylinders.

[blindside]

I've had her for 12 years. So it seems about every 5 years.

[elgringo-inaz]

I am going to change mine today (at least 7 of them).  Two years ago port Exhaust manifold went out.  One plug now frozen but still fires.   Have left that one in as she still runs fine (Just passed 1000 hours). Had boat for 13 years - bought from friend at 80 hours....

[Capt Rick]

Reason to change plugs every year......
The engine does not have a o2 sensor , so it overfuels and the fuel get to go into exhaust manifold. If the engine is under high load for wake boarding then there can be iignition of fuel mixture in the exhaust manifold causing a crack and allowing water into exhaust valves while sitting. So you end up failing the Lexus engine. I recommend using Autolight 3923 gap at .0043. Two engine had same failure this year.
Also by changing spark plugs you can see if any water is there, and can do a compression check.
Capt Rick

[sailtl]

Did mine EVERY year. Every fall after fogging the engine and rolling over once

[Wet-N-Frugal]

As I commented in the original post, if the engine is missing or running rough, changing the plugs is justified... and it's what I would recommend as the best first step to rectify the problem. 

[brad]

Here's another possible reason - dirty MAF Sensor.

http://www.epicmarine.com/forum4/index.php?topic=2455.msg18853#msg18853

[elgringo-inaz]

OK, replaced starboard exhaust manifold. Totally corroded and developed recent leak. Two new manifolds over last two years (one each side).  Hopefully she keeps going and going and going...just over 1000 hours now.  Cleaned MAS as prior to manifold leak she would stall at idle once warm (maybe manifold had something to do with that too). Anyhow changed 7 out of 8 plugs (Even PB Blaster overnight can't loosen plug - plug still fires). Going to leave plug in for now and deal once it fouls (hopefully never).

Snorted up real nice in the driveway with the garden hose....going back to her home at lake on Sat for the real test.

Fingers crossed she is back to normal....

[elgringo-inaz]

A few pics...you would think my boat has been in a wet slip floating in the water it's whole life!  Nope, it is stored on trailer dry storage under roof and in Arizona! Dry Dry Dry! Yet the rust and corrosion on these manifolds is crazy.  The port side looked the same.

[Capt Rick]

The boat when put away with a hot engine will have alot of moisture, but it looks like stray galvanic corrosion. Do you have a  charger hooked up or a light bulb? Do you disconnect battery ?  Take a sample of the water you boat in and see the PH levels.

I have seen that in salt water applications.


Capt Rick

[blindside]

Yep, looks like salt water corrosion.