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2003 530 5 speed
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Discussion Starter · #1 ·
Here's the straight dope for a 2003 530 six cylinder.

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

Please note the attached pdf notice from NGK. The important point is that all NGK
Spark Plugs are manufactured with special shell plating on the metal body that does not require Anti-Seize.

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

I stongly urge anyone replacing plugs on an aluminum cylinderhead to use a torque wrench.

I just replaced my original factory plugs today at 42000 miles, and there is a clear improvement in the smoothness of the engine as you climb through the upper RPM range when shifting gears.
 

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Freude am Fahren
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That clears up any confusion!
 

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What the heck is "torque angle"?
 

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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.
 

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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:
 

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2003 530 5 speed
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Discussion Starter · #6 ·
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?
 

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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.
 

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2003 530 5 speed
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Discussion Starter · #8 ·
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).
 

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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.
 

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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...ly-4-spark-plug-thread-heads.html#post9424574

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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.
 

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Seek to understand,^Value
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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)
 

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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.
 

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

You have a plug in your hand, fit a socket to it.
 

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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.[/i]
Different motor, different head does not make a specification for a BMW head.

It's not stated if cast iron, compacted iron or aluminum head.
 

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Different motor, different head does not make a specification for a BMW head.

It's not stated if cast iron, compacted iron or aluminum head.
A quick google search shows that this is aluminum head.
99.999% of cars out there use Aluminum head.

I understand that this is Ford and not BMW but when it comes to cyl head spark plug hole aluminum threads, they are very similar in principles.

The bottom line is: there is some margin for safety when torquing sp plugs according to BMW guidelines.

Most damage done by amateurs (when changing sp plugs) is from cross-threading, and not so much from over-torque.
 

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Most damage done by amateurs (when changing sp plugs) is from cross-threading, and not so much from over-torque.
+1. AND, you really cannot trust the accuracy of a torque wrench at that low of a setting unless it is rated in in/lbs. Most torque wrenches are rated for accuracy in the upper 80% of their adjustment range. So use at the bottom of setting....at your own risk! So do not use the typical 15lb to 150lb wrench for spark plugs.

Use an in/lb wrench with a range of 2lb to 20lb or there about.

I just tighten until I seat the plug, then turn it until I feel the gasket yields and stop. Never had one come loose....yet. ;)
 

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A quick google search shows that this is aluminum head.
99.999% of cars out there use Aluminum head.

I understand that this is Ford and not BMW but when it comes to cyl head spark plug hole aluminum threads, they are very similar in principles.

The bottom line is: there is some margin for safety when torquing sp plugs according to BMW guidelines.

Most damage done by amateurs (when changing sp plugs) is from cross-threading, and not so much from over-torque.
I'll bet you, even guarantee you that the design of the plug holes in each head are different and therefore the results do not apply to BMW head.

I agree on cross threading being the biggest problem by far.
 
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