Changing spark plugs - do I need Anti Seize?
- Thread starter tripleM
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LOL I know most of the older reps and tec's @ NGK and have been a * NGK distributor on and off since the 70's NGK even sponsored me at one time and can tell you they all will tell you officially not to use anti seize, "wink wink" but they all use it on their own engines. LOL
*I use to buy NGK by the wirght of the pallet and not the number of plugs...
If I’m taking them out, new ones are going in.
For example, Volvo specifies 60,000 miles for their plugs, which are Iridium, but every set I’ve pulled at 30,000 has visible loss of center electrode. So, new ones go back in. I don’t re-gap Iridium plugs, because that loss of center electrode changes the shape of the electrode.
I just pulled them out of both cars. Twin Tip Denso Indiums. One had 35k miles on it the other 45k. A quick spray and brush and re gap. Good for another 25k at least and the Gen Coupe picked up 2 mpg by closing the gap a bit more to .028.
4 cylinders so it's only a 20 minute job.
I reuse my oil filters too.....
But how many are professional mechanics or tuners with 100's of tunups under their belt? Even then (look - I didnt type "that said"!)Seems the responses are pretty much 50/50.
the chances that same car comes back to YOU specifically for round II 30-60 k miles down the road is very low.
I have had no issues with long reach plugs in aluminum heads. What is most important is to NOT over torque in to a hot pentroof cyl head.
I have applied a tiny dab of AS on Autolite plugs, as they don't have the trivalent plating - they are just blued.
Never near the gasket and never near the firing end.
On gasketed plugs I just crush the crush washer and give it a little more to snug it up.
You cant trust a torque wrench in these circumstances. But if you have no experience - use one.
If you overtorque you could unseat the insulator and make the plug run hot.
- Ken
Why would anyone go to the trouble to remove a spark plug that has used up it life and *then re-gap (*that is the clue of a worn spark plug
) and re-install them? Next time you pull them out check there continuity and OHM with a digital volt ohm meter and then tell us all you reused them. You realize an OEM coil X-amount of energy (aprox 40kvolts) to fire a spark plug and as a spark plug wears the ohm becomes greater taking more coil energy to fire the spark plug and create a good high energy kernal for the best combustion of gasoline. So when I keep reading people "going to distance" and claiming no loss in MPG or engine performance ....frankly it BS! lol
The "follow the mfg. instructions" tone regarding anti seize on plugs has turned a corner....... this time around. Not surprising.
Worn? Maybe heat cycling has changed it but the iridium pucks aren't worn. Why would anyone throw out a spark plug with 50k miles of life left in it?Why would anyone go to the trouble to remove a spark plug that has used up it life and *then re-gap (*that is the clue of a worn spark plug
lol
And when I re gap to .028" , originally I gapped them at .032"
These aren't you old Champions you know. And I have the Fuely data tracking receipts to prove it!
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Needs footnotes. Source?
Depends on the brand of plugs used.
NGK claims not needed due to their Trivalent plating.
Denso, doesn't advise against it, but warns that you should reduce the torque by 30%, and less is more when it comes to using anti-seize
NGK claims not needed due to their Trivalent plating.
Denso, doesn't advise against it, but warns that you should reduce the torque by 30%, and less is more when it comes to using anti-seize
Shel_B
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From NGK:
1. Anti-seize
NGK spark plugs feature trivalent plating. This silver or chrome-colored finish on the threads is designed to provide corrosion resistance against moisture and chemicals. The coating also acts as a release agent during spark plug removal. NGK spark plugs are installed at the factory dry, without lubrication or anti-seize.
Anti-seize can act as a lubricant, altering torque values up to 20 percent, increasing the risk of spark plug thread breakage and/or metal shell stretch. Thread breakage can sometimes involve removing the cylinder head for repair. Metal shell stretch changes the heat rating of the spark plug and can result in serious engine damage.
While I don't have a copy handy, there's also a similar caveat on the Denso spark plug page.
1. Anti-seize
NGK spark plugs feature trivalent plating. This silver or chrome-colored finish on the threads is designed to provide corrosion resistance against moisture and chemicals. The coating also acts as a release agent during spark plug removal. NGK spark plugs are installed at the factory dry, without lubrication or anti-seize.
Anti-seize can act as a lubricant, altering torque values up to 20 percent, increasing the risk of spark plug thread breakage and/or metal shell stretch. Thread breakage can sometimes involve removing the cylinder head for repair. Metal shell stretch changes the heat rating of the spark plug and can result in serious engine damage.
While I don't have a copy handy, there's also a similar caveat on the Denso spark plug page.
Ok I am only commenting not asking you to explain.... but I will use your response as a blanket example so don't take offence!
why in the world would anyone go to a smaller gap on a old spark plug......in a Dailey driven run engine?
This clearly shows NO understanding of how spark plugs and the 12 volt ignition system works!!!
In the response I am using as an example what not to do the OP clearly is saying his spark plugs are worn and must compensate by a DIY thought to decrease the spark plugs gap and continue to use them ?
Speaking of spark plug gap... these are only recommendation set by the spark plug manufacture and the Auto manufacture for simplicity and determine a so called best excepted gap for a wide range of use and engines. Engineers contrary to what many often think seldom if ever test for a different gap.
So no one ever wonder why your Brigg and Stratton lawn mower may use the same gap as your Chevy 454 or you Porsche ,BMW, Toyota, weed eater, etc... LOL
Um.. so better be careful and never to damage the threads because it is exactly that a coating and can be scratch off!! Then what do you have.
That's why you don't overtorque them, or undertorque them, you get it just right.Um.. so better be careful and never to damage the threads because it is exactly that a coating and can be scratch off!! Then what do you have.
Even with anti-seize, if you don't reduce the torque, you end up overtorquing them and end up damaging the threads.
This is inaccurate but I am cutting fine hairs. It hard to over torque a spark plug if using the quality and calibrated tools. If you look at the pictures I posted how to properly use anti seize on spark plugs these can be installed as per factory or spark plug recommendation without fear of pulling a thread..
But I will agree for most people it is far better to reduce the torque value but for the main reason very few DIY and even few Auto technicians and mechanic calibrate ther Torque wrench's on a regular basis. And I often go to my friends house and see there torque wrench still at the setting they last used it. I will say as an example oh you changed your head gasket and they reply how did you know that? Another procedure DIY and mechanic often forget ....to re-set ther torque wrenches to zero or lower when they are finished using it.
If I'm paying someone to replace my plugs, they better **** well have calibrated torque wrenches and use it properly.
Many home mechanics don't use a torque wrench or have one and go by how many quarters of rotation to tighten a spark plug... and some manufacturers still provide the "quarters of a turn" instructions depending on gasket type. The 3/4 turn for flat gasket and 1/16 for conical gasket... then you need to remember to do mental math for 30% of 3/4 or 1/16 of turn.
Then again, there are lazy mechanics that are ASE certified that screw something up like putting lug nuts/bolts on... where they just impact wrench the lug nut/bolt on and call it the day.
Back before the Toyota, VW gives you the torque setting for the oil filter cap/housing (cartridge) and oil filter (canister) for when you need to do oil and filter changes... the home DIY'er complains about breaking the plastic housing on them... gee I wonder why???? I never had issues, since I hand-tightened to prevent cross threading and then use a torque wrench for the final torque, so later removal is easy peasy.
They weren't worn. I reduced the gap from when I first installed them. And Hyundai has the wrong gap and Denso pre gaps them at the wrong gap.. They say .044 and you will blow the spark out with that. They have since reduced it to .032. I do know my spark plugs and ignition.
Why would anyone go to the trouble to remove a spark plug that has used up it life and *then re-gap (*that is the clue of a worn spark plug
lol
Agreed. Unless I inadvertently pulled obviously nearly new AND expensive plugs I'm not putting old regapped ones back in. The exceptions would be putting an old plug in if I'm otherwise stranded or don't have the new plug or a emergency, etc. Or if I just bought a vehicle with unknown service, pulled the plugs, and they are clearly new and not needing regap.
Example, I just pulled some plugs and they were Iridium, with unknown mileage. Could be between 5k or even 70k. They would have needed to be regapped from .04 to .031. That's some wear. No idea the age. New ones went in.
Usually plugs are a PITA to get to, and involve some level of hassles and risks of damaging a plug, a plug boot, little plastic fragile clips, etc. If I'm pulling a plug that's obviously worn, a new one is replacing it. Period. I don't want to have to do the job again even 1 year sooner than normal.
