Who uses a torque wrench for spark plugs?

I’ll start off by say in this is NOT a question of should you?

The question is - DO YOU?



I personally have never used one when installing plugs.
And don’t even own a Wrench that has a small enough setting for them.
(Actually, I do but don’t trust it)

My buddy has a Ford F-150 that has blown 2 plugs right out of the head.
He was a mechanic and engine builder, so he knows what he’s doing.
It was a bad design on the 4.6/5.4 where too little threads were used for the aluminum heads.
Anyways, he does recommend using a TQ Wrench on those engines for precautionary reasons.

Until now, I never gave it much thought?

And let’s not turn this in to a Ford bashing thread.
All manufacturers make mistakes and have design flaws.
Even I owned a Ford Lightening with 5.4 and Supercharged.
I did change the plugs, didn’t use a wrench, and “got lucky” I guess?

 

I do.

 

yeah those 3v fords were bad news lmao.

i had to extract all 8 out my dads 5.4, fun time.

 

Bout wrist tight ought to do it.

 

Never have.

I start the plug by hand with the plug on the extension. Add ratchet, turn until gasket contact, then add 1/4 turn. Done.

 

I don't use a torque wrench, because I use anti-seize on the threads which invalidates the FSM torque value. For new plugs I do half-turn with the ratchet handle past hand tight. Did this on a couple of 2nd gens, my Subaru, and yearly on my lawn mower (Honda engine, aluminum head).

 

Installing spark plugs in aluminum heads? I do use a torque wrench.

Installing spark plugs in iron heads? I do not use a torque wrench.

 

Thats a whole separate argument I've seen on forums. whether to use anti-seize or not. NGK actually plainly says not to, as all their plugs have a chromium plating. Supposedly it can also cause grounding issues and some other problems. I've never seen any of that, but I trust the guys making them. I'm sure you won't have any problems either.

Those Ford Triton heads were terrible. I saw tons of blown out spark plugs when I was an automotive machinist. The problem was so bad that a number of companies actually made tools to replace/repair the threads.

To answer your question, I don't use a torque wrench. I run them in by hand with the extension, then tighten until I can kinda feel the crush washer compress.

 

NGK does this to avoid confusing people. The torque specs will be different for dry- and lubricated threads. This is true for most threaded joints. The FSM torque was intended for dry threads. Applying anti-seize and torquing to FSM spec results in overtightening. However, tightening to an angle is immune to these friction coeff changes caused by lubricants.

In the 1GR, removing the factory plugs (which were installed dry) feels really rough with grinding sounds after just 3 years. I wonder how it would be after 5-6 years.

Put it another way - almost ALL the bolts on the truck were manufactured with some form of coating to guard against corrosion. Yet rusted and stuck bolts still occur often. "The guys making them" don't care for these inconveniences once the part is past warranty.

 

Me too. Then another 1/4 uggs dugga. Gently.

 

Torque wrench always.

I've never used antiseize on a spark plug. Denso and NGK say "do not coat the screw thread with lubricant".

 

I figured the Anti-seize topic would arise.

I’ll add that, I almost always use it on vehicles not matter what the head material is made of.
Never have used it on my small engine equipment.
And when I do use it, it’s a LIGHT coat on the thread.
In the grooves is fine , on top of the threads is too much.

 

FWIW......I've always used the copper based anti-seize on sparkplugs.

Learned a hard lesson with a frozen plug. Since then, just a light track on one side of the threads is sufficient. No need to Rembrandt the things. The extra just rolls up under the gasket and turns into a ring shaped blob of goo around the plug.

 

I respectfully disagree. NGK is not the only mfr who says this. And coatings have come a LONG way since our trucks were new. Ive tested many different coating in engines (main bearings, piston crowns, piston skirts, valve faces, cylinder head chambers, etc etc) and they make a huge difference. I also see the amazing technology available in coatings for carbide endmills every day. I have a 12mm endmill running in a part I programmed in which tool life was increased from 2 hours to 5 hours with nothing more than a coating. That's a long time when it comes to roughing titanium. I've stopped using antiseize on plated sparkplugs and haven't seen any issues. Just sharing my thoughts on the matter.

 

I'm on the anti seize train, first time i did my plugs i thought i was going to snap them clean off in the head. Second time around they came out like butter. i dont care what "coating" they use it sucks.

 

Denso says “reduce TQ by 30%”

I didn’t use a wrench, and did them the same as I always do.
Don’t have the slightest of an idea what the TQ I applied to them was?

I might not use any next time, see how it goes?
I don’t know though?

At the risk of being “bashed” - I’ll say that the 30k replacement interval probably isn’t something I adhere to. (But it might be) Mine have been in there “a while”. And that’s all I’m saying about that

 

I've never had a problem and I install them dry in everything. But I haven't always. Only since they've began plating them. But hey, if anti-seize is working for you, I'm not judging, just adding to the discussion.

 

Being an old phart, I've never used a torque wrench on plugs. I have developed a feel for the washer crushing over the years. So far so good.

 

I use a torque wrench and I use anti seize. I don't use a lot and I reduce the torque as recommended.

 

Steel plugs in aluminum heads - you bet!