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Iridiums

ShooterDiesel

Jet Boat Addict
Messages
31
Reaction score
6
Points
102
Location
leonardtown, maryland
Boat Make
Yamaha
Year
2011
Boat Model
SX
Boat Length
24
Just changed out my iridium (ILFR6B) plugs during 100ish hours maintenance. Probably about 80 hours on these for the last 4 years. I probably didn't need to change them. Any thoughts? I've had the boat in The Potomac, Hawaii and now back in the Potomac. Never had an issue with them. Although the new ones replaced them with just fired like champs, smooth.IMG_2799.JPG
 
They don't look too bad minus the rusted ends. I always get nervous when I pull the plugs and see a bunch of rust on the end. Its usually that really good fuel we all are getting. I feel like the quality of fuel even when you get the non-ethanol fuel is just not what it used to be.
 
Is it the ethanol that causes that rust color? I just pulled and changed my plugs (probably didn't need to either), but two of them at the top of the threads had a little spot of red rust color. Not as much as in this picture. Only, say .5mm x 2mm spot.

Not really unhappy or anything. Plugs were in 2 years and I am at 85 hours now. But I was kinda wondering...
 
Rust on plugs = GARBAGE!
A little more rust buildup, next thing you know the plug is stuck in the head and snaps off when trying to remove. Even the ANTI-SEIZE ( which EVERYONE uses on their 4-stroke right????? ;) ) ,doesnt prevent that rust from forming.
Ask Kawasaki 4-stroke owners about this. Every 25 hours on these machines the plugs MUST be removed/replaced or at least inspected to prevent this. and it happens on Yamahas quite often too.
 
@ISLANDRACING Wonder if you have an opinion on those iridiums, I have not been able to see any difference in the past.
Just did mine and used the regular LFR6A.
I stopped using anti-seize on mine, not to mess with heat dissipation. But change them often enough and am not in salt. Probably doesn't matter.

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I put iridiums in on my last big servicing, 4 years ago and a few deployments plus relocating from VA to HI to MD. I've fogged and kept the oil clean. There is no buildup in on the tip, which I thought was amazing. I only replaced them with more iridiums because they were the same price as regular with a $40 off coupon to Advanced Auto Parts(~$60 for 8). The corrosion at the tip of the threads is strange to me. I anti seized them when they went in and they came out easy. No rust anywhere I can see in the system, must be the fuel???
 
I put iridiums in on my last big servicing, 4 years ago and a few deployments plus relocating from VA to HI to MD. I've fogged and kept the oil clean. There is no buildup in on the tip, which I thought was amazing. I only replaced them with more iridiums because they were the same price as regular with a $40 off coupon to Advanced Auto Parts(~$60 for 8). The corrosion at the tip of the threads is strange to me. I anti seized them when they went in and they came out easy. No rust anywhere I can see in the system, must be the fuel???
One thought would be if you ever use anti-knock /octane booster additives such as torco - anything with MMT will leave the rust-like residue. It is not supposed to be bad, just looks weird.

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I love iridium plug and use them in everything, but it could be a disadvantage in the yamaha since you could leave them in too long. I will have to add remove and re anti-seize to my Winterizing list. Cam.
Ps my last dirt bike i never took the iridium out other than to anti-seize it when new. 7 years, maybe not good.
 
Personally, I think the iridiums would be wasted, given my use profile. My 2012 has 86 hours on it. I simply do not run the engines enough to justify something that will last so long. I will be replacing the plugs every 2 years at least, so that I don't have issues with them corroding in place. For that, my regular plugs work fine.
 
I took the boat out on the Potomac yesterday. The difference was very noticeable with new plugs. I won't wait so long to change them again. February boating was great, except the frigid water.
 
They don't look too bad minus the rusted ends. I always get nervous when I pull the plugs and see a bunch of rust on the end. Its usually that really good fuel we all are getting. I feel like the quality of fuel even when you get the non-ethanol fuel is just not what it used to be.
Agree!!! Not only fuel no better but is more $$$
 
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