white crud on 10mm bolt ... what is it?

[jetboater4life]

All of the 10mm bolts that hold my plug cap/boots on the pluts had a white crud that seemed crumble off when I took them out to do a plug change. Is this some sort of locktite? It doesn't seem like it is needed.

 

[JC6275]

Was this your first plug change? If so I would say it is a factory lock tite, or lubricant.

 

[jetboater4life]

For me yes but the plugs were supposedly changed by the dealer I purchased from in TX Fall of 2012. I've not heard of anyone mention about re-adding the loctite/lubricant so I'll assume I don't need to do anything else.

 

[Gym]

It's most likely an anti-seize compound to prevent the plugs from seizing in the head. We have learned, the hard way, that the plugs can break off in the head due to rust caused by water remaining in the cooling system. I would coat the plug threads with anti-seize, NOT Locktite, before reinstalling

 

[Boat Crazy]

I believe it is some form of lock tite and very common to have it there on these boats. After changing plugs yearly for 3 years, I still have it visible. I just continually remove the bolts and reinstall.

 

[Bruce]

Does it smell sweet?

 

[spaz1868]

Does it smell sweet?

If it did smell sweet, what would that indicate?

 

[Bruce]

If it did smell sweet, what would that indicate?

That it is Loctite 567 thread sealant which Yamaha uses other places on our boats.

 

[jetboater4life]

I didn't think to smell it. No one has ever mentioned adding it to those bolts so I don't think I need to worry about it. I was just curious. Thanks for the comments.

 

[davel501]

Service manual page 5-36 has it as Loctite 572

 

[jetboater4life]

Service manual page 5-36 has it as Loctite 572

Nice find. Maybe I will put a dab on them when I change next year.

 

[itsdgm]

I'm pretty sure it's on mine too. But I've never added any when reinstalling.