Sealant required on spark plug boot bolts.

[beachbum]

Quick question... while changing the spark plugs on our sx190... the manuals suggest "loctite 521" sealant on the bolts that secure the spark plug boot.

What is a usable equivalent sealant for this purpose?

 

[tdonoughue]

I would think that any of the silicone-like spark plug boot goop you get at an auto parts store would work fine. Should not be anything particularly 'marine' needed.

 

[itsdgm]

Not sure exactly what you're referring to @beachbum. I use dielectric grease on the inside of my Coil Over Plug (COP) where they come in contact with the spark plug and where it seals out water at the top of the plug tube. But it sounds like you might be referring to the bolt on top of the COP that secures it to the valve cover. I don't use anything there. Just be careful not to over tighten, because one of mine is on the verge of stripping out. The valve cover is much softer metal than the bolt.

Keep in mind that I have the MR1 engines, so yours could be totally different.

 

[Big Shasta]

It might not be a bad idea to put some low strength Loctite on them, probably not necessary but it can't hurt. I've never read of one coming loose.

 

[beachbum]

sorry didn't respond yet guys... was playing on the lake ALL day with the boat.

Thank you for the replies.

I don't think a critical "sealant" ... just going by the book as much as I can.

 

[Bruce]

Permatex High Temperature Thread Sealant is available at most auto parts stores. I used it as a replacement for Loctite 567 on the jet pumps after unsucessfully searching for the Loctite product. I have change my spark plugs three times without using any sealant. I have not seen any issues so far.

 

[beachbum]

Thanks all for the replies... wondered how "required" it was since just a sealant... not that sealants aren't good with our marine products...

 

[dan144k]

Loctight 521 is a white paste. I think it is 567. It is similar to a thin pipe dope. I put a little never seize on the bolts. I use to use the white paste. Some blue leak lock would be ok too

In the manual yamaha also tells you to use the 567 on the impeller threads. I had thread problems at one point and had to replace the shaft. Talked to dealer about and he said to always use never seize onost things on the boat.

 

[Cobra Jet Steering LLC]

I always put dielectric grease on the plug boots, and its very important to use never seize on the plug threads I actually do that before ever using a new engine, but the coil bolts I don't put anything on those and I have never had one come loose.