2016 sx192 Spark plugs

[David Gramig]

Bought our boat last fall haven't used it much but always like keeping spare parts with me. I am having troubles finding what plugs are used and the factory gap? Any help appreciated I did try to search for them and found the NGK Part number LFR6A but cant verify those are the proper plugs. Any help greatly appreciated.

 

[Joe Hellaby]

Yup, that's the right NGK part number. They come pre gapped. But the gap is .8-.9mm or .031-0.35in
The NGK iridium part number is iLFR6B

 

[David Gramig]

Joe,
Thanks for the quick response. I know there are many different opinions on iridium plugs, but if I change them regularly do you recommend the iridium?

 

[Joe Hellaby]

I don't use iridium plugs, there's been a lot of discussion on here from people who use them and don't. I would use iridium if I did not fog the engine (as they should last a lot longer). However, I fog the cylinders in the fall, put the old plug back in, bump the engine, and then in the spring pull the old plugs out and replace with new. I suppose you could use iridiums and just clean the fogging oil off every spring with one of the spark plug sandblasters or something like that.
Just my opinion, I look at it as one being a great long lasting plug, and I would rather replace with new cheaper ones more often.
(and this is only my second season boating, so I'm still learning what works best for me)

 

[David Gramig]

This will be my second season also. We bought our boat late last fall and only got out a few times. I feel the same way you do about the plugs and just plan to change them each year. Cheap investment for piece of mind. I plan to change mine in the next few weeks and keep the old ones as a back up. Thanks for all your input

 

[swatski]

Joe,
Thanks for the quick response. I know there are many different opinions on iridium plugs, but if I change them regularly do you recommend the iridium?

The fastest 1.8 jet skis (and boats) that we know of run with OEM (LFR6A) plugs. I ran iridiums in my 190 and would not consider those as an improvement by any stretch.

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[Jetswu87]

I'm pretty sure my stock plugs in my 15 SX192 were the Iridium's already. I could be wrong, if they aren't I'm with you guys I run standard copper plugs in everything else.

However if they are Iridium's.....

These are 100k mile plugs in standard vehicles, and even in some forced inducted vehicles such as WRX's call for changing at 30k miles. Not sure the love affair with swapping iridium plugs once a season, pull them..inspect replace as needed. PS check the gap on the plugs but be very careful gaping iridium plugs, also inspect the porcelain on them well. I've had a few of these over the years cracked out of the box that would only misfire under heavy load.

I had 30 hours on the boat last season, pulled plugs for fogging and they still looked brand new.

 

[Eric N]

I'm replacing the plugs on my 2015 AR192. I can't find the proper torque specs for the plugs and don't want to strip the aluminum head. Does anyone know how tight to torque them down? Thanks!

 

[swatski]

I'm replacing the plugs on my 2015 AR192. I can't find the proper torque specs for the plugs and don't want to strip the aluminum head. Does anyone know how tight to torque them down? Thanks!

Most people would say - hand tight and then 1/4 turn.
Hopefully someone who actually knows will chime in!
Keep in mind that IF using anti-seizing compound the torque values no longer apply. Many members here do not use it. The argument goes both ways, but grease effects heat dissipation.

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[FLBulldogger]

Eric,
I pulled my plugs and replaced them and did an oil change using this video from Leon Adler

if you dont want to watch the video for its entirety (even though Leon did a great job of keeping it entertaining and informative, fast forward to about the 25 min 41 sec portion and he gives the torque settings, I do believe he has a 2013 or 2014 and he used anti seize, so not sure if its a valid setting considering @swatski 's advice. And if you don't want to watch at all (spoiler alert) he advises 18.4 ft lbs of torque.

 

[Midnight2V]

There's a couple of important things regarding spark plugs to remember with these being supercharged engines. It's not just plug dimensions that determines cross-compatibility.

Being supercharged, they will have a different heat range than a NA plug. This difference is identified by the depth of the void along the element inside the outer housing. The depth of the void adjusts the heat dissipatation qualities of the inner conductor.

Different plug manufacturers will spec their heat ranges according to varying criteria, including electrode material itself. If the engine were naturally aspirated, it would hardly be an issue at all. For forced induction, it can be very important to preventing detonation.

As far as electrode material, iridium is chosen for its best in the periodic table resistance to corrosion, second highest density in the periodic table, and very high mechanical strength. Ironically, it is not a particularly good conductor at normal temperatures.

It is its density and corrosion resistance that makes it a desirable material in spark plugs because it loses so few atoms during each arc event, and has them so tightly packed. This is why iridium has such high intervals between changes, especially extended high rpm environments such as marine.

Changing plugs each year is certainly not required, they can be easily cleaned. At about $18 dollars each, I can definitely spend the money better elsewhere.

In short, I wouldn't try substituting plugs unless you are modifying the engine.

If someone insisted on changing plugs each season, I would recommend staying with NGK for the same heat range standards and simply using a copper plug.