Spark plug torque when using anti-seize

Status
Not open for further replies.
Good post Critic.
thumbsup2.gif
 
Last edited:
Originally Posted by 02SE
Are you aware that spark plug indexing washers have been around for decades?

Yes, but that is not part of the OEM service procedure.
 
Originally Posted by The Critic
Originally Posted by 02SE
Are you aware that spark plug indexing washers have been around for decades?

Yes, but that is not part of the OEM service procedure.


Ya I was going to say the same thing. My friend with a sprint car will buy a ton of plugs for one of his engines and just puts in the ones he can index correctly without shims.
 
Originally Posted by The Critic
Originally Posted by 02SE
Are you aware that spark plug indexing washers have been around for decades?

Yes, but that is not part of the OEM service procedure.


Yes I was aware of that but nice post, most people don't. We used to index years ago with indexing washers as someone said, it didn't bring much on the dyno but that was with carbs.

Edit: You can still use anti seize on those plugs just mark the plug base where the electrode is and keep the mark in the range but I would probably just use engine oil on the threads in this case. Where is the NGK fan club and Bosch haters?
 
Last edited:
Originally Posted by The Critic
Originally Posted by 02SE
Are you aware that spark plug indexing washers have been around for decades?

Yes, but that is not part of the OEM service procedure.


Adding forced induction and rebuilding the transmission with better-than-oem parts in my sportscar, is not part of the OEM service procedure either.
 
There is a difference between proper torque and proper indexing

In the case listed if you get the spark plug indexed properly but it is a couple in/lbs off I don't see how that is going to make a difference.

Just because it is indeedx correctly doesn't mean it is torqued correctly
 
Last edited:
Shocking MD engine requires indexed plugs. Looks like they need a plug that does not require indexing - unless they are tring to direct flamfront in a stratified charge which they likely ARE.

Used to index with heads off on our comp cars,. reduced part throttle misfire count and improved perceived cylinder balance.

I rejoice being an NGK hater. Subaru only ran well on ND or Champ. Many Japanese Subaru came with USA made Champion plugs and Packard Ignition wires.
back in the Inconel/Cu plug days of the mid 90's.

What does that tell you?
 
Last edited:
I wish to publicly withdraw my advocacy for not using anti-seize on spark plug threads. As I said earlier in this thread, for the past many years and in many cars and for many miles I had never had a problem not using anti-seize, up until yesterday when I went to change the plugs on my ECHO. They were quite difficult to remove, two were "stuck", one was "really stuck" and the last one I was debating whether to proceed removing it or not because it was so hard to turn. But I did get all four out eventually and the threads looked OK from what I could view. But it was pretty harrowing wondering if I was going to strip the threads and force me to remove the head to repair.

It was weird though, there wasn't any evidence of water or anything getting down in the plug wells and the rubber gaskets under the coils looked just fine. So I don't know why this time out of the many previous times was different, but it was. I put anti-seize on the new plugs and used the torque angle method of installation.
 
Originally Posted by kschachn
I wish to publicly withdraw my advocacy for not using anti-seize on spark plug threads. As I said earlier in this thread, for the past many years and in many cars and for many miles I had never had a problem not using anti-seize, up until yesterday when I went to change the plugs on my ECHO. They were quite difficult to remove, two were "stuck", one was "really stuck" and the last one I was debating whether to proceed removing it or not because it was so hard to turn. But I did get all four out eventually and the threads looked OK from what I could view. But it was pretty harrowing wondering if I was going to strip the threads and force me to remove the head to repair.

It was weird though, there wasn't any evidence of water or anything getting down in the plug wells and the rubber gaskets under the coils looked just fine. So I don't know why this time out of the many previous times was different, but it was. I put anti-seize on the new plugs and used the torque angle method of installation.



It entirely depends. Some plugs are plated so you don't want to use anti-seize and doing so could cause a problem.
 
All the ones I've installed were plated, either Denso or NGK. I will say that the majority of the ones I've put on in the past were Denso, only lately have I been using NGK.
 
Huh. I never knew using anti-seize required backing off the torque. I just installed 8 new Champion copper core plugs in my son's 04 Grand Cherokee 4.7 V8. The torque spec is 20lbs for the plugs. I used a little anti-seize and stayed with 20lbs.

Why would the use of anti-seize require this? Does it act like a thread locker?
 
Originally Posted by IndyFan
Why would the use of anti-seize require this? Does it act like a thread locker?

Exactly the opposite, as indicated by its name.

It is a lubricant - lubricants reduce friction, so you need to apply less torque to achieve the required tension on the fastener.
 
We have a torque formal for the use of anti-seize for fasteners on submarines. It even depends on the material of the fastener. It is very specific.

Like I said as far as sparks plugs go, a little won't hurt. If something goes wrong you can just pull over.

It tends to be a little more important on submarines for obvious reasons.
smile.gif
laugh.gif
.
 
FWIW I just did plugs in my 2000 Ford 2 valve 4.6 which has a reputation of spitting plugs and I did them at 20 foot pounds with a dab of antiseize. Ford says not to under tighten them as that's what causes them to spit out of the head. It also depends on the size of your plug.
 
I don't understand why applying anti-seize to the threads would have any bearing on the torque applied. All the anti-seize does is prevents the threads from locking together when removing the plugs...
 
Last edited:
Originally Posted by grampi
I don't understand why applying anti-seize to the threads would have an bearing on the torque applied. All the anti-seize does is prevents the threads from locking together when removing the plugs...


That's because torque is directly related to the coefficient of friction of the threads. Most torque specs are provided for dry, clean, freshly machined threads.
Applying any lubricant to the threads will reduce the coefficient of friction and therefore alter the torque wrench reading in the sense that it will take more rotations to achieve the same TQ reading vs. clean and dry threads.

Rust alters the torque reading in opposite fashion. Because if the increase in coefficient of friction, it will take less rotations to achieve the desired torque. Therefore the fastener will in reality be under torqued.
 
Status
Not open for further replies.
Back
Top Bottom