That clears up any confusion!

 

What the heck is "torque angle"?

 

It's used for torquing bolts to a yield point, which slightly stretches the bolt, providing an optimum clamping action. The bolt cannot be used again.

The bolt is tightened to a specific torque value, and then tightened further to a specified angle. The wrench has an angle measuring device, almost like a protractor.

 

It's used for torquing bolts to a yield point, which slightly stretches the bolt, providing an optimum clamping action. The bolt cannot be used again.

The bolt is tightened to a specific torque value, and then tightened further to a specified angle. The wrench has an angle measuring device, almost like a protractor.

Got it.

Problem is the *.pdf file states : "When installing spark plugs without special metal plating (with anti-seize), install based on vehicle manufacturer's torque angle."

My E46 Bentley manual states plugs are to be torqued to 25 NM (18 ft-lb.)

I've never heard of torque angle being used to torque plugs. It's not like it's a steel bolt. You just put enough juice behind it to compress the crush washer.

So I was just wondering WTH they were on about talking "torque angle" for spark plugs. It doesn't make any sense. :dunno:

 

My E46 Bentley manual states plugs are to be torqued to 25 NM (18 ft-lb.)

Wingspan, does your E46 use a 12mm spark plug?

 

Hmmm...it's listed as a OEM NGK BKR6 EQUP.

I think I used a 17mm to do the plugs (M54 engine), but I'm not sure.

 

Hmmm...it's listed as a OEM NGK BKR6 EQUP.

I think I used a 17mm to do the plugs (M54 engine), but I'm not sure.

Great, another can of worms. :rofl:

Here's the PDF for BMW Torque Specs. Go to Page 52 for spark plugs (as posted).

 

A little dab of anti-seize on the threads will not do any harm.
Just reduce the torque a bit.

NGK should have published two separate torque values, one for dry and one for anti-seize installation.

Best is to remove spark plugs every 2yr or 24K or so for examination and apply a dab of anti-seize to prevent bonding.
I have done this for 30 years and always use 25 Nm, never have a single problem with all my cars.

 

A little dab of anti-seize on the threads will not do any harm.
Just reduce the torque a bit.

NGK should have published two separate torque values, one for dry and one for anti-seize installation.

Best is to remove spark plugs every 2yr or 24K or so for examination and apply a dab of anti-seize to prevent bonding.
I have done this for 30 years and always use 25 Nm, never have a single problem with all my cars.

Hello Cam.
Actually this would force you to change the VCG and the grommets too. I just go with the 4 -5 years / 80,000 Km interval. So far so good.
Back in the day, me and my dad used to change them plugs every year. And service the goddam' carburator once or twice a year. One must love todays cars.

 

For those who wonder what torque is necessary to strip the cylinderhead spark plug hole's thread. This fellow from the Ford Forum did this experiment using a junk Ford engine. Read this for fun:

http://www.ford-trucks.com/forums/1...-for-the-breaking-point-on-the-early-4-spark-plug-thread-heads.html#post9424574

----------
QUOTE:
I used a scrap Ford 2001 MY PI 2V V10 head with good threads to test the breaking point of the plug threads that are so weak according to many people on this forum.

I did four plugs, two with antiseize and two dry.
I started with the correct torque and worked up.

At 55 ft lbs it felt like the threads were just starting to stretch.

From 55 to 85 I got about 1-1/2 turns more out of them, and it did not feel good.

Two of the plugs snaped off flush with the heads just shy of 100 ft lbs, after anouther 3/4 turns from 85 ft lbs. One was dry and one had anti seize.

The third plug broke right at of 100, 5/8s of a turn after 85 ft lbs. This one had anti seize.

The forth made it to 115 ft lbs, 1/8 turn past 100 ft lbs (7/8s of a turn passed 85 ft lbs) and snaped. This was a dry plug.

Every one of them the plug broke, I never striped the threads out of the heads like I though I would.

 

experiment using a junk Ford engine

I love this type of real-world autopsy information!

The only other way to get this information is to try it on our beloved BMW.

This thread (which I hadn't known about prior) belongs in the bestlinks (so, I just added it).

- Selecting and changing your spark plugs (1) (2) (3) (4) & the truth about torque (1)

 

1+,

Torque wrench is a must when Installing Spark Plugs:
http://www.ngk-sparkplugs.jp/english/techinfo/qa/q18/index.html

--------------------
--------------------
However, when you don't have the Torque Wrench, you can follow NGK procedure here.
NOTE: "new" and re-used". Also one turn is defined as 360 degrees.

 

My point about this thread spark plug vs anti-seize (I always use anti-seize) is that: there is room for error ---> Let's say the book says 30 Nm, if one goes to 25Nm or 35 Nm, no big deal (some people panic over this little change in torque).
The sp plug will break at 100 lb-ft or roughly 130 Nm (see experiment above).

FYI, my 2007 Honda Odyssey calls for 13 lb-ft (same plug design and dimension as my E39, same aluminum head thread number). I think 13lb-ft is a tad low.....so I use 18-20 lb-ft.

A little trick was taught to me by the pro many years back: during install, I always a tiny dab of anti-seize on spark plug threads. Then turn the sp plug socket by hand in Counter-clockwise direction a few times to avoid cross-threading. Then turn it Clockwise to tighten it, again by hand only. Use the ratchet only when you cannot turn it by hand any more.

NOTE: Sometimes, the sp plug SOCKET's rubber insert broke with time/use ---> sp plug installed at wrong angle (see last picture above)!
If the rubber insert is broken, get a new socket or use the appropriate hose as a fix.
The hose I use has I.D. = 8mm and O.D. = 17mm; just cut a small donut and insert it in the socket (remove the old rubber insert 1st).

 

Using 20 lb-ft intead of 13 lb-ft is ~ a 53 % increase in torque, a gross disregard of the spec and the work that went into designing the spec.

Most folk think they know better than the Engrs that spent 1000s of man hours designing and testing the threads and plug designs. I suppose it it easy to take this approach if one does not have a real Engr education and experience in an auto mfgrs design office with very extensive testing laboratories.

The design engrs are responsible for 100s of 1000s of vehicles with 4, 6 or 8 plug holes each and want and need to get it correct. Generations of engrs in the auto companies and also in the plug companies have worked on plug threads and know better than the man on the street or any one mechanic with 20 or 30 yrs experience. Think about it.

Regarding the anti-seize, I use it on most threads but not plugs as its not required. If you do use it it must be very high temperature rated. If not it will bake into the threads in the head and some will remain there after the old plug is removed interfering with the installation of the new plug.

Regarding the reverse turning before starting the thread to help align it, I agree. Most of us do this every day with milk cartons, bottles of water, etc. We turn the cap backwards and when feeling the click and the cap dropping down we know to stop and then begin tightening the cap as well as the spark plug and many other items with threads that we encounter daily.

 

One way of preventing cross-threading and other thread-starting problems is to use a length of rubber fuel line or any other hose that fits snugly over the porcelain jacket of the plug....insert the plug into the hose, gently insert the plug into the plug hole, and turn the hose to start the threads and run it down into the head. This method gives more sensitivity than using a socket & extension.

(BTW, I`m Old School.... I believe in anti-sieze on plugs, and I`ve learned to trust my hands for the proper torque value....sorry, doubters)

 

...(BTW, I`m Old School.... I believe in anti-sieze on plugs, and I`ve learned to trust my hands for the proper torque value....sorry, doubters)

Fast Bob,

You are not Old-School. You are smart.
I use antiseize as well.

And despite the fact that Honda, BMW, Toyota etc. tell us not to change sp plugs until 100K miles, I remove them every 3 years for inspection, apply antiseize and put them back in (if I re-used the sp plugs). After all, these mfg's do not have to deal with seized sp plugs at 100K, we have to deal with it!

Even the pros at Popular Mechanics recommend antiseize. And I can tell you these guys at Popular Mechanics know their stuff!

http://www.popularmechanics.com/cars/how-to/repair/4212608

A: There are a number of ways to repair stripped threads. In fact, it may be possible to simply chase the old threads with a tap and clean them up. Or, as illustrated, you can insert a Helicoil. There are several types of repair inserts, but we prefer Helicoils. I'd give your mechanic a shot at fixing the threads before I held his feet to the fire. When a spark plug has had a chance to marry a cylinder head for 100,000 miles, it's not uncommon for the aluminum threads to come out of the head with the plug. (I pull and inspect plugs every couple of years and reinstall them with a small dab of antiseize compound, but that's another column.)

 

For the record, I updated the bestlinks with new E39 spark plug information:
- BMW spark plug application charts (1) (2), best plug to use (1) (2), deciphering key (1), reading plugs (1), the truth about torque (1), the truth about gap (1) (2) & DIYs for replacing spark plugs (1) (2) (3) (4) (5)

And, here is a summary (for another thread) of the PDF in the first post of this thread:
E39 (1997 - 2003) > The Truth About Spark Plug Torque and Anti- Seize

1. The OP starts off with the "straight dope":
   • Quote:
     

     When replacing your spark plugs with the factory recommended NGK BKR6EQUP, do not apply Anti-Seize compound

     *******> ********>
2. He then covers the recommended torque without anti-seize compound:
   • Quote:
     

     you can now torque the NGK BKR6EQUP plug to the BMW factory specified 30 NM dry (for this 14mm plug).

     *******> ********>
3. Then he provides the recommendations from NGK regarding the use of anti-seize compounds on this plug:
   • Quote:
     

     Topic: The use of anti-seize compounds on spark plug threads that have a "special shell plating" (i.e. Trivalent coating).

     *******> ********>
   • Quote:
     

     Issue: Applying anti-seize to the threads of spark plugs that have a special metal plating thus allowing the installer to mistakenly over-torque the spark plug in the cylinder head. Over-torque stretches the metal between the last thread and the seal between the cylinder head and spark plug, causing a much higher probability that the spark plug will either break during installation or upon removal.

     *******> ********>
4. Then NGK goes into the solution:
   • Quote:
     

     Solution: For spark plugs with special metal plating; anti-seize is not recommended during installation.

     *******> ********>
5. Then there is some additional information from NGK:
   • Quote:
     

     Additional Information: It is recommended to use spark plugs with the special plating on all aluminum cylinder head applications to prevent damage to the cylinder head. All NGK Spark Plugs are manufactured with special shell plating on the metal body.

     *******> ********>
6. NGK then discusses when to use anti-seize:
   • Quote:
     

     The use of anti-seize on spark plugs is only recommended on those brands that do not offer a special metal shell plating. Spark plugs that have a shiny silver appearance on the metal body usually indicate that the spark plug is manufactured with special metal shell plating.

     *******> ********>
7. Then NGK cover torque angle for plugs that lack special metal plating:
   • Quote:
     

     When installing spark plugs without special metal plating (with anti-seize), install based on vehicle manufacturer's torque angle. These images show spark plugs that do not have special metal shell plating where they have bonded with the aluminum in the cylinder head

     *******> ********>
8. And NGK again covers their recommendations on the use of anti-seize:
   • Quote:
     

     When using anti-seize:Only on spark plugs without special metal plating. Use manufacturer's torque angle to avoid over-tightening

     *******> ********>

 

nvm

 

2001 e-39

525i base wagon. Anti seize?

 

A bit more info about NGK plugs.
In the past not all NGK plugs had the anti-seize coating applied and an an anti-seize was needed to prevent seizing in alloy heads.

RonR

 

Not to resurrect the dead...

I was researching the torque spec and came across this and had to post my issue the OP post. I am not dogging the guy... its always good to pass on Manufactures literature and information. Just wanted to comment on an experience that was contrary to the Manufacture's documented information.

I pulled NGK plugs out and thought ii was going to break each one off. For the first 3-4 full turns I felt that grab/release/tight feeling.

I will be installing A/S on the replacements.

 

Here's another from first hand experience:
That Ford V-10 head is frim the Triton V-10, which up to 2003 has a reputation for blowing the spark plugs out. And I mean it breaks the coil and all. Very little in the way of threads on that. Too tight rips the threads out, too loose lets it start out and clears the last threads out while running. Correct kit for repair is about $225 with inserts, and I have one on the shelf by my bench.
So. That head is no way like a BMW.
Next.
A bit of neverseize wont hurt it. If you can tell that the car runs better with or without neverseize....I promise it was something else.
I have replaced an incredible number of sparkplugs in my life, BMW, Boat Motors, American Iron, Motorcycles, literally everything. Only used a torque wrench on that Triton because it is so marginal. Never had a problem.
Next point; Don't take spark plugs out just to inspect and reinstall. (i'm gonna hear a lot of manual Thumping here!!) Only take them out to find a problem. Ie compression, a misfire etc. They are platinum and very good long lasting plugs. Best way ever to screw up something is to mess with it when it was working fine.
When you do take spark plugs out, float test them. Take them to the lake and toss them in. If they float they are ok to reuse.


Sent from BimmerApp mobile app

 

when you do take spark plugs out, float test them. Take them to the lake and toss them in. If they float they are ok to reuse.

Sent from bimmerapp mobile app

lol

 

Installing and torquing spark plugs to specification

Incredible some of the comments above. NGK does not include advise on their proprietary "coating" with the spark plugs they sell>>>period. However, their little chart on 1/2 turn/ new plugs; 1/4 turn 'used plugs" has worked for me for 30 years on aluminum heads (without a torque wrench). That's what I did at 94,500 mi. on my M62TU and now at 114K mi. after replacing plugs. That said, I replaced one coil for good cause then and waiting for the rest. I use some anti-seize on the upper threads, lightly as I do want the plugs to ground AND I want them to come out IF...steel and alloy expand at diff. rates.:thumbdwn:

 

Re antiseize: I use the equivalent of one drop of water (from a volume standpoint).
Once the spark plug is torqued down, there is nice contact between the threads and the cylinderhead anyway.
From a grounding principle, not an issue at all.

I have never had problem with one drop of antiseize.

 

There is a good discussion, today, over here, which says that the typical gray anti-seize isn't designed for high-heat applications (such as for spark plugs):
> E39 (1997 - 2003) > Safest way to remove stuck spark plugs ?

I can tell you with 100% certainty that anti seize is not designed for high heat applications. The oil in the base heats up.. bakes out, and leave a concrete like paste which is just about as good as lock tight

Of course, this thread also has a lot of information about what NGK and BMW think about spark plug anti-seize...
> E39 (1997 - 2003) > Pictorial DIY for an M54 spark plug replacement on a 2002 BMW 525i E39 with 95K miles

 

I just pulled the plugs out of my 528i and after almost wrestling with them i finally got then out.
The old plugs are ngk laser plat. And they have some corrosion and i can't put the new ones in for fear of stripping. Should i use anti seize.
What to do?

 

The Bentley shop manual, which is the official BMW technical manual, states to use a small dap of copper anti-seize on the spark plug threads. This is in spite of the NGK plug manufacturer saying it is not recommended or necessary. I still use anti-seize, because BMW must have a reason for the recommendation, that is contrary to NGK.

 

I've been using anit-seize for the last 30 years, no problems here.

 

Bentley probably made their manual from looking at the BMW TIS, in addition to taking a vehicle apart to photo many parts of it for their manuals.
Just this last Jan Bentley finally came out with their X3 manual. How long has the X3 been in production? Maybe 10 years??

The silver anti seize stuff is what I use on exhaust studs and the plugs. The copper stuff really stinks when it starts to burn off on the exhaust studs.

 

Bentley probably made their manual from looking at the BMW TIS

I never studied it, but it seems that most (all?) of the diagrams in the Bentleys come from BMW, so, there must be some relationship, I assume.

Maybe Bentley pays BMW for the use of their diagrams?

The silver anti seize stuff is what I use on exhaust studs and the plugs. The copper stuff really stinks when it starts to burn off on the exhaust studs.

That's interesting. I haven't researched what sacrificial metal the gray paste is made out of.

I know Permatex does a special "nickel" paste; but I don't know what metal is in the "regular" paste for our aluminum engines.

Maybe zinc?

 

Since were are talking about antiseize, what is best for exhaust and suspension bolts? CRC metal free turns into dust..

 

For the crosslinked record, there is a thread on Bosch plugs backing out, where the consensus seems to be that the real problem is torque, perhaps exacerbated by the use of anti-seize sacrificial anode paste ...
> E39 (1997 - 2003) > Why would Bosch spark plugs be prone to loosening & backing out & needing timeserts?