I worked at an auto parts store long enough to be aware of certain issues. Why do we stock three spark plug repair kits? Because we sell them.
Then, I'm forever the guy harassing all my friends with the crown vics and f150s and expeditions. You still have all your plugs?
I want to avoid that experience.
Is best practice to use motorcraft plugs, anti-seize, and exact torque? Is there a better method?
wae
UberDork
11/13/20 11:48 a.m.
On the 6.8 V10, the "trick" that seems to work is blasting past the factory torque spec of 17ish ftlbs and tightening the plugs to about 30.
I thought another manufacturer produces a better 1 piece spark plug?
When I owned a 3 valve 5.4 F150, the internet consensus was to soak the plug wells in penetrating oil and carefully loosen the plugs 1/8th of a turn, then tighten again. Repeat multiple times over several days and the chance of success goes up dramatically.
YMMV and all that...
EDIT: Oh, you're talking about the 2 valve Modular engines that spit the plugs out. Reading comprehension fail
I recently read something about not using anti seize on plug threads, because it lubricates the threads and you end up putting a higher load on them than you’d think when torquing the spark plugs down. Not sure if it’s legit or not.
I seem to recall you need to go higher than the factory’s original spec for the plugs, but you also can’t go too high or you strip the threads.
I have read that the early years of the 5.4 and 6.8 had less threads for the plugs to screw in to so they would fail. Later heads were machined with more threads.
Best practice for the ones that eject themselves is to replace without anti-seize and torque higher. I don't usually go as high as 30, but my elbow torque wrench says about 22.4773.
Earlier heads only had three "wraps" of threads in the heads. They didn't keep the plugs tight at 17 ft-lbs, and the ant-seize made it worse. They worked a little loose and the constant compression/vacuum just battered the heck out of the threads until they pop out taking the threads with them... and usually breaking the coil at the same time.
The later ones had plenty of threads, but they had the issue of the super long insulator to get the electrode in the chamber. They get carboned up and much of the time you pull the plug out only to realize that the nose has remained in the hole requiring the extractor.
Had mine replaced in a rare "farm it out, I don't wanna deal with the possible fallout" moment. Gave them the truck on a Friday, they oiled it while it was hot and let it sit till Monday and had no trouble.
07expedition with 5.4
I think you're beyond that with the marquis de sade, aren't you?
On my ‘01 Mustang, I torqued the plugs slightly higher than the spec (IIIRC 17ft-lbs vs. 13). Never had an issue.
Apexcarver said:
Had mine replaced in a rare "farm it out, I don't wanna deal with the possible fallout" moment. Gave them the truck on a Friday, they oiled it while it was hot and let it sit till Monday and had no trouble.
07expedition with 5.4
I did the same with my 03 Grand-ma-quis. At 80K i started getting a stumble if pushed (rare.) I figured prolly not worn plugs, but possibly some fouling from being babied its entire life. The shop had a tech that is known in the area as a bit of a 4.6 enthusiast. Had had no problems prior, and none since... crossing my fingers! Stumble also went away, but 8K later (more little old lady miles) and is back, but intermittent. Still 20.8 mog, so doesn't worry me much.
In reply to Patrick (Forum Supporter) :
I'd heard it was only the earlier models with the habit of ejecting plugs. But I've also heard it was only the two valves, and I've had folks tell me it was only the three valves. And I've heard anti seize is mandatory. And I've heard to never touch the stuff (generally good advice I think).
So much junk floating around that I thought I'd ask the hive.
For the record, this is a 2005 2-valve 4.6. 102k and no service records.
Just to start the conversation off on a contentious note, you'd have to be a berkeleying moron to put antiseize on a spark plug.
Now that we are past that, torque them properly, if you feel one start to loosen off just before you get it tight, go buy an insert and rethread the hole.
The only plugs I've ever seen come out of an early Ford triton were installed by a moron.
There. Three drinks in, and I've offended a bunch of people. My job here is done.
In reply to Streetwiseguy :
I generally dislike anti-seize so I think I can refrain.
consensus seems to be to slightly over torque the plugs.
Do we have a better plug? I generally like to use oem. Which means motorcraft. But I also like NGK plugs.
Of my friends who actually had plugs fly free, both farmed it out. One had the broken hole fixed and all the plugs replaced, only to have another let loose a few weeks later.
Very few places I will farm work out to. Hey, I can do half azz work all by myself! One of the shops I trust in the area, unfortunately trust their parts supplier... he is sometimes 4 times high on the parts he sells them. I forget to check first sometimes, so I guess that's my fault - $600 for a AC compressor for my wife's highlander. For just the part! And I didn't catch it till afterwards. But the work is good, and we can drop the car off after hours with out worrying about stuff in it. Their house is on the same property.
Plugs in an aluminum head always get anti-seize. Always. I've seen too many of them come back out with all the threads from the head stuck to them.
As for the Fords, I replaced the plugs in my 5.4 a couple of times using anti-seize and no torque wrench. It ran 200k without spitting one. Just make sure they don't get loose.
Toyman01 (Moderately Supportive Dude) said:
Plugs in an aluminum head always get anti-seize. Always. I've seen too many of them come back out with all the threads from the head stuck to them.
As for the Fords, I replaced the plugs in my 5.4 a couple of times using anti-seize and no torque wrench. It ran 200k without spitting one. Just make sure they don't get loose.
I've only been a professional mechanic working on stuff with aluminum heads since 1980, so you could be right, but 40 years of not using antiseize is good enough for me. The only plugs I've ever had stuck in an aluminum head involved antifreeze in that cylinder.
Building subs ( the Navy kind, not the subway ) taught me to use antiseize on everything! Also taught me it should be used very sparingly. You don't have to slop it on with a 4"paint brush. 'Course we used MolyCoat, unless it was high heat, and then it was FelPro copper. The power plants use nickle based on everything. Haven't done a lot with alum. heads, but a small amount of antiseize seems like a good plan. Hint: if it splatters when ya put it in the hole, you prolly used to much. Unless ... never mind.
I'm in the don't anti seize any spark plugs ever group. I've worked on cars most of my life with several years doing it professionally and I've never had a problem. The garage I worked at before moving back to a simpler job mostly did Buick so my mod motor experience is only backyard stuff helping friends.
03Panther said:
Apexcarver said:
Had mine replaced in a rare "farm it out, I don't wanna deal with the possible fallout" moment. Gave them the truck on a Friday, they oiled it while it was hot and let it sit till Monday and had no trouble.
07expedition with 5.4
I did the same with my 03 Grand-ma-quis. At 80K i started getting a stumble if pushed (rare.) I figured prolly not worn plugs, but possibly some fouling from being babied its entire life. The shop had a tech that is known in the area as a bit of a 4.6 enthusiast. Had had no problems prior, and none since... crossing my fingers! Stumble also went away, but 8K later (more little old lady miles) and is back, but intermittent. Still 20.8 mog, so doesn't worry me much.
You check the coils out? Mine was doing similar and I had a bad coil. Replaced it and it runs great.
Have not really thought about it (if it ain't broke, don't fix it) and not very bad yet. But upon reflection, I would 'bout guarantee you are correct.
I respect folks' opinions, but when Ford says you should use anti-seize, I'm going to do it.
Note: This is for the 3V engines which want to hang on to their plugs (or, at least parts of them), rather than eject them like the 2V ones.
In reply to Apexcarver :
A little bit of google fu, and I may have to try new boots first. Even though the shop that did them is a bit better, the plugs were still done by a guy making pay by how quick he can get the job done. Not a great environment for getting things done well! No offense to any individual... there are always a few that can do it right despite the environment. But you guy's are the exceptions!
I only do anti-seize if a particular engine exhibits problems when you don't use it in a certain application.
But millions of aluminum-head outboards, cars, trucks, generators, lawn mowers, chainsaws, and all other forms of ICEs get by just fine without it.
I have pulled a few thousand OEM spark plugs out of aluminum headed engines and almost never see anti-seize from the factory... except in 2v 5.4L Fords, and they have problems that are partially caused by using it. At least millions of 5.4L owners report that NOT using it when they replace plugs has solved the issue.
2 valves had the plugs that blew out. Ford used the same tooling to cut the plug threads as in their iron heads: half the threads were missing so the plugs would self-align when installing, kind of like bullet nose wheel studs. Works great on iron heads, aluminum not so much.
If you went 80k on the original plugs, just go ahead and replace all the coils too. Yeah, they "say" the plugs are a 100k maintenance item, but what that means is, if you haven't changed them yet, get them out of there already! Worn plugs require higher voltage to build in the coils to jump the gap, this breaks down the windings faster. They might be okay "now" but they'll start failing soon. Fords are especially prone to coil failure for whatever reason, probably because they're tiny little things on the Mod motors.
(Never had a problem with not anti-seizing normal plugs. If the threads gall, it's because of carbon stuck on the end of the plug, and anti-seize ain't going to help you there)
Tom_Spangler (Forum Supporter) said:
I respect folks' opinions, but when Ford says you should use anti-seize, I'm going to do it.
Note: This is for the 3V engines which want to hang on to their plugs (or, at least parts of them), rather than eject them like the 2V ones.
On the 3V, go for it. But the fact that a manufacturer said something almost makes me more skeptical of it. Do I want the advice of the company that did something they thought would be good and sent it out into the world with no idea? Or do I want the advice of the thousands of techs and owners who have seen how things work over the course of millions of trucks and millions of miles?
We're talking about things like Ford issuing a TSB to lower tire pressures on explorers and people died, or GM saying "yes, Dexcool is wonderful stuff" while it choked on contractually-obligated warranty repairs to millions of wasted cooling systems. Or Oldsmobile's procedure for fixing failed head gaskets on the 350 diesel by re-using the old head bolts.
Having been on "that" side of the dealership, I know that what actually comes out of the mouths and brains of the engineers is almost never what gets published after it gets sifted through marketing and execution.