That thread about greasing spark plug threads ..

[spitfire4v8]

I can't find the actual thread I wanted to, but I was in the minority of people who use an anti-seize compound when installing spark plugs.

Yes Chimpongas I read the NGK help file you linked to once or twice about the use of greases (though it is more to do with over-tightening than any particular issue with spark plug function) .. but I will always use something on the threads, and last night just before heading home it reinforced to me exactly why I do.

The most inconvenient thing happened to my own car, and now my cheapo workhorse Focus is rendered (for the moment at least, or maybe permanently) an expensive ornament / door stop / car park hazard.

Yes, a spark plug snapped off in the head, and yet again the ever-faithful Tuscan is pressed into commuter service. Thank goodness for reliable TVRs, and also parts installed on cars with a view to long term maintenance... ie anti-seize greases.

I don't care what anyone says, not even NGK. I will always grease spark plug threads.

[TwinKam]

Seconded.
I have no idea how many spark plugs I have fitted in my 40 years of working (but... simple maths... it would be between 40,000 & 80,000!), none of them were fitted without antiseize compound/ copper rich grease.
No plug I have fitted has snapped through overtightening, nor was ever reluctant to be removed, which is more than I can say about engines being seen by me for the first time, including (or rather, especially) those with a main dealer service history. And 'Long life' plugs lying undisturbed for up to 60,000 miles has made this situation far far worse.

[nawarne]

Also - Seconded!!

Always use copper anti-seize when ever I change plugs.....In fact I try to apply to any bolts I've taken off when I replace them.

Nick

[Andy JB]

nawarne said:

Also - Seconded!!

Always use copper anti-seize when ever I change plugs.....In fact I try to apply to any bolts I've taken off when I replace them.

Nick

+1 17 years on my TVR no issues plugs always removed no problems

[N7GTX]

The problem seems more to do with conical seat plugs. The ordinary ones with a sealing washer never seem to give problems unless its the old lack of maintenance issue.
I use ZX13 which was used extensively on jet pipe fittings on military aircraft. Works up to 800c.

[fieryfred]

I agree. I cheat though, i use the dip stick to oil the threads. Easy in easy out. Goes against the grain but i also just nip the plug up then unwind, then tighten that ensures the crush washer does its job. Never had a problem getting one of my plugs out, but i have cursed the Gorilla who dry fitted them before me.
I never dry fit any bolt, even locktite provides lubrication.

[ukkid35]

TwinKam said:

And 'Long life' plugs lying undisturbed for up to 60,000 miles has made this situation far far worse.

I'm sure I'm not the only one who could see that problem coming a mile off