Loctite at top part of 787 head cover bolts and grease on the threads?

[GGuillot]

I'm doing assembly and it seems unusual the shop manual calls for Loctite 242 on topside of the bolts and synthetic grease on the threads? Only on the 787 head cover part, everywhere else it's the opposite. Is this a mistake?

 

[tobytd]

Just did mine that way - all good

 

[mikidymac]

Yes, that is actually correct. The grease on the threads allows proper torque and the loctite seals the bolts from water.

 

[Dr Honda]

I just coat the threads in antiseze, and put the engine together. I've never seen head shell bolts vibrate out if they were in good shape, and clean when put back in.

 

[GGuillot]

Thanks for the responses, just checking.

 

[Mekanix]

Yes do it exactly how it says to in the manual. Weird but yes it works.
Also the grease is there so that you can actually remove the bolts after years of corrosion.

 

[GGuillot]

Corrosion prevention later, makes sense, also what's weird is 2 out of 8 bots on the exhaust manifold to cylinder head is flipped, synthetic grease on threads of 2, then loctite 515 on threads of the other 6.

 

[Mekanix]

Yes those go into the water jacket. It could leak otherwise.