FYI spark plug change caution

[drcoffee]

I just changed my spark plugs on the wife's 2000 Villager with 80,000 miles. They must install them dry at the factory because these were some of the toughest plugs I've ever removed. It makes me very uneasy removing plugs from Aluminum heads when they are stuck as mine were. Had I known, I would have pulled them out when new and added anti-seize. Number 5 plug took the tap (plus some) of an impact wrench with liquid wrench sprayed on it. Unforunately the crush washer decided it liked the head better than the spark plug and it stayed as a permanent part of the head. It was still smooth and the mating surface of the old plug was clean and smooth too, so I left it rather than chiselling a chunck into the cylinder through the plug hole. All the others came out rough but in good shape.

It's nice that Mercury uses high quality plugs to last 100k miles but a little lube to help remove them in 8 years would be a reasonable consideration. If you ever plan to change your plugs down the road, I would suggest that you pull them now and add some hi-temp anti-seize today to make it easier later on.

[QuestOverload]

I agree, matter of fact I'm afraid to take the plugs out of my blue van; it acts like it might take the threads right out of the head if I took the plugs out.

Steel and aluminum can basically weld themselves together over time due to a chemical aluminum, and anti-sieze can prevent this, so in other words, you'd be nuts to NOT use anti-sieze.

I also agree about the factory, I wouldn't mind going back and telling them how f'ing crazy they were for not putting anti-sieze on in the first place! It's not a Nissan/Ford thing either, seized plugs are the #1 cause of cylinder head replacements on 4 cylinder GM products because people believe the 100K tuneup schpiel and tear up the heads trying to change the plugs.

[drcoffee]

I don't believe in "torqueing" spark plugs ever! I palm the wratchet and squeeze them in place on aluminum heads. Usually its about 6-8#s. You just need to seat the plug and crush the gasket, nothing more.

As for your situation I had purchased a 1996 Explorer a few years back with 60,000 miles on the clock. It was obvious the plugs were original so I made the change. The #2 plug would not come out for 3 days. I just sprayed it with liquid wrench 5 times a day and rapped it with very short bursts from the electric impact wrench. If I had to say how long a burst is, I'd say it is equal to 3 impacts and then off, repeat 5 times. Any more than that and you may shear off the plug. The impact wrench helps the liquid wrench penetrate. And once it does the plug usually comes out. But it took 3 days before the plug came out of the iron head truck of mine. Just have patience and take your time.