Lube spark plug threads?
Thread Starter
MBWorld Fanatic!
Joined: Jun 2002
Posts: 7,263
Likes: 169
From: So. Oregon Coast
C230 Sport Coup + 2006 W164 ML350 + 99 Ford Escort RIP
Lube spark plug threads?
OK, I've replaced spark plugs many times, but
when unscrewing the ones currently in my car, they seemed to
feel a little funny. And squeaked when tightening.
I'm wondering, should I put some Anti seize compound on the threads?
Or would that cause them to vibrate out?
I had that happen once, a plug worked it's way loose and shot out like a rocket, ricocheting under the hood at 60 mph.
I was incredibly lucky as it lodged itself onto a bumper bracket, and I was able to reinstall it and make it home, especially since it was dark, and I was on a country road. I never woulda found it!
Of course the threads were stripped, and I eventually put a helicoil in there,
but that ended up getting stuck to the plug dammit.
Anyway, don't want plugs flying out, nor do I want them welding themselves to the head. What sayest our mechanically inclined members?
BTW, I have oh 40K-50K miles on my NGK Iridiums, 2 steps cooler, and they are looking great. A nice tan color which is good. The gap is even still correct.
Probably didn't need to replace them, but what the heck.
when unscrewing the ones currently in my car, they seemed to
feel a little funny. And squeaked when tightening.
I'm wondering, should I put some Anti seize compound on the threads?
Or would that cause them to vibrate out?
I had that happen once, a plug worked it's way loose and shot out like a rocket, ricocheting under the hood at 60 mph.
I was incredibly lucky as it lodged itself onto a bumper bracket, and I was able to reinstall it and make it home, especially since it was dark, and I was on a country road. I never woulda found it!
Of course the threads were stripped, and I eventually put a helicoil in there,
but that ended up getting stuck to the plug dammit.
Anyway, don't want plugs flying out, nor do I want them welding themselves to the head. What sayest our mechanically inclined members?
BTW, I have oh 40K-50K miles on my NGK Iridiums, 2 steps cooler, and they are looking great. A nice tan color which is good. The gap is even still correct.
Probably didn't need to replace them, but what the heck.
MBWorld Fanatic!
Joined: Nov 2001
Posts: 5,851
Likes: 196
From: Huntington Beach, Ca.
'17 Jaguar XF
Yes...just a small dab though. If you use too much it will melt and find its way to the electrode and foul it. Supposedly Bosch plugs are plated so they won't seize but people/mechanics report they can seize if you leave them in too long. My theory is they only seize if water gets in the plug galley and accelerates corrosion.
