VonoreTn Posted November 22, 2015 Share Posted November 22, 2015 (edited) I'm trying to replace my spark plugs at 121K miles, which I thought would be an easy job, but I find they are all turning at about 40-50 ft lbs, and not getting easier. I'm used to a plug maybe starting hard but then getting easier to turn. I think that is in the range of breaking the plug hex, so I stopped after about 1 turn on each of them. The engine was cold, maybe I should do it with a hot engine? I guess we all can envision the subsequent problems if I break or strip a plug down that deep hole, going into the aluminum head. Edited November 22, 2015 by VonoreTn 0 Quote Link to comment Share on other sites More sharing options...
lolder Posted November 22, 2015 Share Posted November 22, 2015 Do you think you could run a tap into it without getting debris in the cylinder? How easily did they come out? 0 Quote Link to comment Share on other sites More sharing options...
VonoreTn Posted November 22, 2015 Author Share Posted November 22, 2015 (edited) Hi Lee, I didn't get them out, because they never stopped turning at 40-50 ft lbs. It was a jerky turn, like reach a threshold, then it would drop from 50 ft lbs to 40 ft lbs, but right back to 50 ft lbs for the next increment. The jerk is scary, you think you broke something or stripped the hex each jerk. I think right now, I'm going to tighten them back up, and try just one again when the engine is hot. The aluminum head might expand enough with heat to make a difference. But in answer to your question, I think if I get them out, I will put some anti-seize thread lubricant on the new ones. These plugs are not like you and I are used to, the thread engagement is very long, like just under an inch, which is probably part of the situation. A lot of steel against aluminum, for the last 6 years, could be some galvanic action. This situation might be a rationale to replace the plugs at lower mileage and time, even though based on performance, they are still functioning fine. The manual says to replace plugs at 100K miles. Edited November 22, 2015 by VonoreTn 0 Quote Link to comment Share on other sites More sharing options...
VonoreTn Posted November 22, 2015 Author Share Posted November 22, 2015 (edited) I got them out, after soaking the top of the thread area with PB blaster for 2 hours. The gap range is from .054 to .057", a little above the spec. of .049-.053". The new NGK LTR5GP plugs are all at .042" gap. I guess I have to open them up to .049. Apparently you can run your plugs for a long time these days. Edited November 22, 2015 by VonoreTn 1 Quote Link to comment Share on other sites More sharing options...
BlueOval2010 Posted November 22, 2015 Share Posted November 22, 2015 Louder - to answer your question, I'd say there's no way you could run a tap to clean up the threads without fear of getting debris into the cylinder. Safe bet would be to pull the head if something bad happens. Also, anti-seize compound will have an effect on torque settings when reinstalling the plugs. 0 Quote Link to comment Share on other sites More sharing options...
VonoreTn Posted November 22, 2015 Author Share Posted November 22, 2015 (edited) Louder - to answer your question, I'd say there's no way you could run a tap to clean up the threads without fear of getting debris into the cylinder. Safe bet would be to pull the head if something bad happens. Also, anti-seize compound will have an effect on torque settings when reinstalling the plugs. I torqued them to 17 ft lbs, the spark plug box said max of 14 ft lbs in an aluminum head, but 17 felt about right. Edited November 22, 2015 by VonoreTn 0 Quote Link to comment Share on other sites More sharing options...
Buster1 Posted November 23, 2015 Share Posted November 23, 2015 (edited) Vonore, What caused you to want to change the plugs initially? Is there a recommended service interval? I'm also curious as to how the car performed or if your gas mileage improved with new plugs. Side note: I just put fresh tires on my FFH. 82,000miles (mostly hwy) on the originals! Edited November 23, 2015 by Buster1 0 Quote Link to comment Share on other sites More sharing options...
lolder Posted November 23, 2015 Share Posted November 23, 2015 I noticed that the thread is very long. The anti-seize shouldn't matter as it isn't a pipe thread and just a shoulder seal. I'm going to talk to my mechanic about it.The steel on aluminum is certainly a worry now that you might go ten years before plug changes. 0 Quote Link to comment Share on other sites More sharing options...
akirby Posted November 23, 2015 Share Posted November 23, 2015 You don't want to go more than 100K without at least removing and reinstalling the plugs - otherwise they get stuck. 1 Quote Link to comment Share on other sites More sharing options...
VonoreTn Posted November 23, 2015 Author Share Posted November 23, 2015 Vonore, What caused you to want to change the plugs initially? Is there a recommended service interval? I'm also curious as to how the car performed or if your gas mileage improved with new plugs. The manual says change plugs at 100K miles. I'll let you know after we get back from a 2400 mile Thanksgiving trip to Austin and Gulf Shores if there is any impact on mileage. Since the plug gaps are slightly smaller now, which means not quite as big a spark, I don't expect any improvement in mileage. But if I continue to get around 40 mpg, I will be happy. My long term average for 120K miles is almost exactly 40, which included a lot of bad condition driving, like up hill into the wind over several states. You did better on your tires than I have, I'm averaging about 70K miles, I change one tire at a time, as it gets down to the wear nubs. I buy them on-line and have them put on at local dealers. 0 Quote Link to comment Share on other sites More sharing options...
VonoreTn Posted November 23, 2015 Author Share Posted November 23, 2015 You don't want to go more than 100K without at least removing and reinstalling the plugs - otherwise they get stuck. Good advice. Not that hard to do, maybe even put some anti-seize on them at 50-60 k miles. Don't get any near the electrode. 0 Quote Link to comment Share on other sites More sharing options...
nygard1 Posted January 17, 2018 Share Posted January 17, 2018 I am having the same problem with very tight spark plugs on a 2008 Fusion 2.3 with 135k miles. I am afraid that I might strip the threads when I pull them out. Was there any thread damage evident when you finally got the plugs out on your 1010 Fusion? 0 Quote Link to comment Share on other sites More sharing options...
FusionDiffusion Posted January 17, 2018 Share Posted January 17, 2018 If they are tight, you might have to spray penetrating oil down the wells and hope it helps (don't use too much though). Another method is to alternate tightening with loosening to try to break the threads free. But at some point you just have to go for it with lots of leverage and hope you don't strip out the threads on the heads. 0 Quote Link to comment Share on other sites More sharing options...
VonoreTn Posted January 17, 2018 Author Share Posted January 17, 2018 10 hours ago, nygard1 said: I am having the same problem with very tight spark plugs on a 2008 Fusion 2.3 with 135k miles. I am afraid that I might strip the threads when I pull them out. Was there any thread damage evident when you finally got the plugs out on your 1010 Fusion? No there was no indication of thread damage. I think everything worked out. I have a friend who runs a tire and chassis garage, and he says he would be out of business without PB blaster penetrating oil. It does stuff at a microscopic level, over a period of time, that is very useful. I have read reviews that Liquid Wrench is just as good, but I am not an expert. I think both are better than WD40, which also works at some level. After applying penetrating oil consider running the engine to put load on the plug threads from the combustion impact, which perhaps at a microscopic level, that will allow the penetrating oil to spread through molecule size passages in the area. I would avoid exceeding 50 foot pounds, because a spark plug structurally is just a thin steel tube with non structural porcelain in it. 0 Quote Link to comment Share on other sites More sharing options...
drolds1 Posted January 17, 2018 Share Posted January 17, 2018 Not the first time I've heard good things about PB Blaster. I have a 21 year-old Nissan Altima with only 48K on it. It's still got the OE plugs in. At this point, they can stay until I'm gone. Runs fine. Dealer said leave 'em alone also. 1 Quote Link to comment Share on other sites More sharing options...
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