DIY: spark plug change - LS400 2000
07-09-18, 05:01 PM
#16
Driver School Candidate
Remove the intake? You mean remove the air intake duct right? Also, use spark plug anti-sieze on the threads, and don't bother with the "remove the rust" tip by OP you are just asking for a stripped thread. Keep a piece of 3/8 hose available to snag any plugs that won't come out of the deep holes after they have been fully unthreaded. Also, use boot grease on the coil boots and inspect all the wiring to the coil. Age is going to affect the wiring and the coil. Oh, disconnect the battery first, or risk confusing your computer.
07-09-18, 05:19 PM
#17
This is the first I have heard of a plug not needing anti-sieze. Doesn't mean they don't exist, but with a packet of anti-seize for a dollar at the check out how could you go wrong.
07-09-18, 05:22 PM
#18
Driver School Candidate
07-09-18, 05:34 PM
#19
Moderator
Autolite
We do not recommend the use of any anti seize products for installing spark plugs. Anti-seize compounds are typically composed of metallic, electrically conductive ingredients. If anti seize compounds come in contact with the core nose of the plugs, it can lead to a misfire condition. Anti seize compounds can also have a torque multiplying effect when installing plugs. This can lead to thread distortion and thread galling resulting in cylinder head damage. Autolite spark plugs are nickel plated to resist the effects of corrosion and seizing. However, plug seizure is aggravated further when steel plugs are installed into aluminum cylinder heads for a long period of time.
AC/Delco
Do not use any type of anti-seize compound on spark plug threads. Doing this will decrease the amount of friction between the threads. The result of the lowered friction is that when the spark plug is torqued to the proper specification, the spark plug is turned too far into the cylinder head. This increases the likelihood of pulling or stripping the threads in the cylinder head. Over-tightening of a spark plug can cause stretching of the spark plug shell and could allow blowby to pass through the gasket seal between the shell and insulator. Over-tightening also results in extremely difficult removal.
Champion
The following material is excerpted from the Champion Spark Plug Handbook. It can be accessed at:
http://dodgeram.info/Engine-Gas/Spar...plghnbook.html
Champion spark plug shells (the threaded part) use an extruded steel to maintain exact tolerances. The extruded shell goes through a cold rolling process to form the threads. This prevents sharp edges which could cut new threads into aluminum cylinder heads. Once the shell is formed and threaded, it is zinc-plated to extend its life and reduce the chances of seizure in aluminum cylinder heads. Our latest technology combines Tin Tac" and ULTRASEAL'M coatings over the plating to further reduce corrosion and seizure. Champion recommends that you do not use an anti-seize compound, since one has already been applied to the plugs at the factory.
Intrigued, I went a-googling for any information I could find from NGK on this topic. I found this excellent Canadian website that lists the complete set of NGK Technical Bulletins. Go to:
http://www.ngkplugpro.ca/en/bulletins.php
Or, you can go directly here for NGK's take on the use of anti-seize compound, NGK Technical Bulletin #NGKSP-0907-1:
http://www.ngkplugpro.ca/content/con...SparkPlugs.pdf
According to the Bulletin, NGK states that all their plugs are manufactured with a special metal shell (trivalent) plating to prevent damage to the cylinder head. For plugs with this special metal plating, anti-seize is not recommended during installation. Applying anti-seize to these plugs will cause the installer to mistakenly over-torque the plug in the cylinder head stretching the metal between the last thread and the seal between the cylinder head and plug. This increases the probability that the spark plug will either break during installation or upon removal.
For plugs without a special metal shell plating, NGK advises the use of anti-seize and provides photos of unplated plugs installed without anti-seize where the steel threads have bonded with the aluminum in the cylinder head requiring replacement or repair of the head.
Denso also warns against the use of anti-seize in their Spark Plug Installation instructions:
http://www.globaldenso.com/en/produc...ion/index.html
Specifically, they state: "If a thread lubricant such as grease is coated on the thread, tightening to the recommended torque is tightening too much; this has been linked to seal leakage. Do not use a thread lubricant."
We do not recommend the use of any anti seize products for installing spark plugs. Anti-seize compounds are typically composed of metallic, electrically conductive ingredients. If anti seize compounds come in contact with the core nose of the plugs, it can lead to a misfire condition. Anti seize compounds can also have a torque multiplying effect when installing plugs. This can lead to thread distortion and thread galling resulting in cylinder head damage. Autolite spark plugs are nickel plated to resist the effects of corrosion and seizing. However, plug seizure is aggravated further when steel plugs are installed into aluminum cylinder heads for a long period of time.
AC/Delco
Do not use any type of anti-seize compound on spark plug threads. Doing this will decrease the amount of friction between the threads. The result of the lowered friction is that when the spark plug is torqued to the proper specification, the spark plug is turned too far into the cylinder head. This increases the likelihood of pulling or stripping the threads in the cylinder head. Over-tightening of a spark plug can cause stretching of the spark plug shell and could allow blowby to pass through the gasket seal between the shell and insulator. Over-tightening also results in extremely difficult removal.
Champion
The following material is excerpted from the Champion Spark Plug Handbook. It can be accessed at:
http://dodgeram.info/Engine-Gas/Spar...plghnbook.html
Champion spark plug shells (the threaded part) use an extruded steel to maintain exact tolerances. The extruded shell goes through a cold rolling process to form the threads. This prevents sharp edges which could cut new threads into aluminum cylinder heads. Once the shell is formed and threaded, it is zinc-plated to extend its life and reduce the chances of seizure in aluminum cylinder heads. Our latest technology combines Tin Tac" and ULTRASEAL'M coatings over the plating to further reduce corrosion and seizure. Champion recommends that you do not use an anti-seize compound, since one has already been applied to the plugs at the factory.
Intrigued, I went a-googling for any information I could find from NGK on this topic. I found this excellent Canadian website that lists the complete set of NGK Technical Bulletins. Go to:
http://www.ngkplugpro.ca/en/bulletins.php
Or, you can go directly here for NGK's take on the use of anti-seize compound, NGK Technical Bulletin #NGKSP-0907-1:
http://www.ngkplugpro.ca/content/con...SparkPlugs.pdf
According to the Bulletin, NGK states that all their plugs are manufactured with a special metal shell (trivalent) plating to prevent damage to the cylinder head. For plugs with this special metal plating, anti-seize is not recommended during installation. Applying anti-seize to these plugs will cause the installer to mistakenly over-torque the plug in the cylinder head stretching the metal between the last thread and the seal between the cylinder head and plug. This increases the probability that the spark plug will either break during installation or upon removal.
For plugs without a special metal shell plating, NGK advises the use of anti-seize and provides photos of unplated plugs installed without anti-seize where the steel threads have bonded with the aluminum in the cylinder head requiring replacement or repair of the head.
Denso also warns against the use of anti-seize in their Spark Plug Installation instructions:
http://www.globaldenso.com/en/produc...ion/index.html
Specifically, they state: "If a thread lubricant such as grease is coated on the thread, tightening to the recommended torque is tightening too much; this has been linked to seal leakage. Do not use a thread lubricant."
Last edited by bradland; 07-09-18 at 06:29 PM.
07-09-18, 05:59 PM
#20
Moderator
Other than spark plugs, the galvanic corrosion is always a key issue when we use dissimilar metals. Some car manufacturers didn't know this well and their products are now causing many problems in the market. For an example, a company called M have used aluminium and copper in the evaporator and this is causing the gas leaking problem a lot.
07-10-18, 02:24 PM
#21
I think this is one of those areas where if you understand what you're doing, you can still do it the best way, using antiseize, which is what I do.
First concern is to not get antiseize beyond the threads, where it could get onto the tip. Yes, avoid that. Not difficult.
Second, MAJOR concern, is to avoid over-torquing, which would be a real disaster if you damage the head. Most spark plugs I use have specifications on torque to angle, including with gasket, without gasket, or re-using the gasket. Typically when using a new spark plug with gasket, it will be (I think) 2/3 of a full turn after finger tight (~first contact). By using a breaker bar rather than a ratchet, I can pretty accurately measure 4 * 1/6 turn = 2/3, getting an extremely accurate "torque" control on the installation and can still use anti-seize.
When you torque anything, what you're really trying to do is control the clamping force without breaking anything. The actual torque is not the true goal, it is the clamping force you're after. Torque to angle will control that more accurately.
I expect that most of the people that write those specifications would agree that this is the better way to do it, but that enough people would screw it up that they advise skipping on the anti-seize and using a torque wrench.
For example, what do you do if you've got a leaking valve cover and some of the threads in the spark plug holes have oil on them? Torque those to a lower value? Get them clean? How clean, and at what contamination cost? None of those are problems with TTA.
First concern is to not get antiseize beyond the threads, where it could get onto the tip. Yes, avoid that. Not difficult.
Second, MAJOR concern, is to avoid over-torquing, which would be a real disaster if you damage the head. Most spark plugs I use have specifications on torque to angle, including with gasket, without gasket, or re-using the gasket. Typically when using a new spark plug with gasket, it will be (I think) 2/3 of a full turn after finger tight (~first contact). By using a breaker bar rather than a ratchet, I can pretty accurately measure 4 * 1/6 turn = 2/3, getting an extremely accurate "torque" control on the installation and can still use anti-seize.
When you torque anything, what you're really trying to do is control the clamping force without breaking anything. The actual torque is not the true goal, it is the clamping force you're after. Torque to angle will control that more accurately.
I expect that most of the people that write those specifications would agree that this is the better way to do it, but that enough people would screw it up that they advise skipping on the anti-seize and using a torque wrench.
For example, what do you do if you've got a leaking valve cover and some of the threads in the spark plug holes have oil on them? Torque those to a lower value? Get them clean? How clean, and at what contamination cost? None of those are problems with TTA.
Last edited by oldskewel; 07-10-18 at 02:27 PM.
07-10-18, 02:39 PM
#22
Common sense people. Don't put anti-sieze on anything but the threads, and dont goop it on. Oh, never trust pre-gapped plugs either. a spark plug isn't holding a part on like a bolt does, there is no need to tighten a spark plug more than the first stop of a ratchet. If you have to muscle it you are gonna mess up the head, break the plug, or cross threading it.
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