To seize or not to seize?

[dadofral]

Changing the plugs in the 2015 212x for the first time since I’ve owned it, should I use anti seize on the threads or no?
It appears they did I not use it previously. Also, what gap are you all using?

 

[Beachbummer]

NGK says we don't need it for our plugs. (Sorry I don't have the direct link, but someone found the docs and posted them on the board some time ago).

I use it anyway. "a thin film away from the very bottom of the threads can't hurt" is my reasoning...but you alone suffer the consequences of your actions, so I wish you luck regardless of how you choose to do it.

 

[tdonoughue]

This has been oft-debated on the forum here. In the one camp are those who point out that adding antiseize changes the torque specs, so you can wind up over torquing your plugs putting them in, which is bad, etc. In the other camp are those who observe that if you leave in plugs too long they can corrode in place--also bad, etc.

Myself, I put antiseize on mine.

 

[Jgorm]

The one time i used it i had 2 plugs back out and ruin the threads. 20+ years of wrenching. Only 1 stuck plug and that was a fx140 and the threads were buggered up.

 

[dadofral]

Thanks for the input. I’ll probably use a little bit then.

 

[Gym]

The one time i used it i had 2 plugs back out and ruin the threads. 20+ years of wrenching. Only 1 stuck plug and that was a fx140 and the threads were buggered up.

Your plugs backed out on a Yamaha engine with that tight coil boot over them or was it on another engine type?

 

[Maillis]

If you’re going to change the plugs every 1-2 years there is no reason to put anti-seize on them, especially when the spark plug manufacturer specifically directs you to not use it with their plugs.

 

[Dixie Highway]

I’d never put antiseize on a spark plug, they may not be able to back all the way out but it’s still no good to have a place for fuel to mix with spark outside the engine.

 

[Gym]

If you’re going to change the plugs every 1-2 years there is no reason to put anti-seize on them, especially when the spark plug manufacturer specifically directs you to not use it with their plugs.

Well, our boat manufacturer said a plastic scupper below the waterline was adequate also. I'd like to hear from those members who broke spark plugs trying to remove them if they use antisieze or not.

 

[Jgorm]

Your plugs backed out on a Yamaha engine with that tight coil boot over them or was it on another engine type?

Ford 4.6 2v.

 

[Looper7]

I am a firm believer in no threads should be assembled dry 30 years in motorsports has taught me lock tite when needed everything else anti seize

 

[Ratket]

If you’re going to change the plugs every 1-2 years there is no reason to put anti-seize on them, especially when the spark plug manufacturer specifically directs you to not use it with their plugs.

Sorry I’m still Laughing...
“ Manufacture specifically “ ...
as long as any manufacturers part gets past warranty or can not be held responsible for the damage it caused when it fails, that’s their goal.

Personally I would put a small amount on it,
Make sure you check ur plug gaps, even if you buy those “ Manufactured pre gapped plugs”, chances are one will be off.

Measure 6 times cut once...


Link to spark plug gap thread-

https://jetboaters.net/threads/spark-plug-gap.23965/

 

[Zeusmotorworks]

Come from aerospace manufacturing background, little SCCA, owned/operated a rally car business (automotive experience), and avid on road motorcyclist. As someone else said earlier, something in most cases goes on threads... will not install spark plugs without copper anti-seize on them (same for lug nuts but doesn't have to be copper). Actually always pull plugs early the first time just to that end. As such, never had a damaged spark plug that a customer hadn't blown the engine on.

 

[Gym]

One wildcard that was brought up years ago on this forum is that these spark plugs are being used in a marine environment. Whereas plug #3 (at least on the MR-1 engines) seemed to be the common plug to break when being removed. It was theorized that it was likely the exhaust valve, on cylinder 3, often remains in the open position when the engine is shut down allowing moisture from the water boxes to rise into that cylinder causing the plug threads to rust. The postmortem on these #3 plugs showed rust on the lower plug threads lending some credibility to this theory whereas the other plugs had no rust.

Anti seize or not is your choice we're still here to help out when you snap a plug. I even anti seize my trailer lug nuts whereas I operate in salt. Happy Labor Day

 

[jEt_jAk]

Not to seize

 

[Jgorm]

It was theorized that it was likely the exhaust valve, on cylinder 3, often remains in the open position when the engine is shut down allowing moisture from the water boxes to rise into that cylinder causing the plug threads to rust. The postmortem on these #3 plugs showed rust on the lower plug threads lending some credibility to this theory whereas the other plugs had no rust.

That theory doesn't make any sense. There is no reason the engine would stop on the number 3 exhaust stroke any more often than the other 3 cylinders. Having said that, i had corroded exhaust valves on 2 and 3. And a suck number 3 on a different mr1, but that looked like it got cross threaded. I think the casting was off on the number 3 cylinder because i had a 3rd mr1 where i couldn't thread the compression tester into.

 

[Gym]

That theory doesn't make any sense. There is no reason the engine would stop on the number 3 exhaust stroke any more often than the other 3 cylinders. Having said that, i had corroded exhaust valves on 2 and 3. And a suck number 3 on a different mr1, but that looked like it got cross threaded. I think the casting was off on the number 3 cylinder because i had a 3rd mr1 where i couldn't thread the compression tester into.

Can't debate that with you @Jgorm. It was only a theory floated by another member. I can give you a fact though. Everybody who snapped #3 and took pics of all 4 plugs in that engine showed rust on the broken #3 threads. Your mention of a miscast causing a crossthread also makes sense. With regard to your corrosion on exhaust valves on cyl 2 & 3. I see you're in San Diego. Do you operate in salt? Also do you fog your engines per Yamaha recommendations? We both run the same generation SX230. I operate only in the ocean so fogging and anti seizing are a standard practice for me. Including on wheel lug nuts.

 

[Jgorm]

I keep my boat at the Colorado River. I don't think it's ever seen salt. My issue occurred on my first trip after buying it from a guy in yuma.

I've spent a lot of time in sd Bay with a variety of boats. Never used anti seize, never had a stuck plug. I've had exhaust manifold with rust holes you could fit you thumb in!

 

[Gym]

I keep my boat at the Colorado River. I don't think it's ever seen salt. My issue occurred on my first trip after buying it from a guy in yuma.

I've spent a lot of time in sd Bay with a variety of boats. Never used anti seize, never had a stuck plug. I've had exhaust manifold with rust holes you could fit you thumb in!

Your #3 plug looks like it has a lot of corrosion at the top of the threads where it connects to the plug body. That's where the plugs tend to snap. Are those plugs more than 1 season old @Jgorm?

 

[tdonoughue]

Wow. Now, I am in fresh only. So that is the disclaimer. My plugs never look that rusted at all. If mine looked like that, I would certainly be putting on the antiseize.

That said, I think that annual changing of the plugs matters. If you diligently replace annually, the need for antiseize is greatly reduced.