![]() Suspension Tech and Handling sponsored by.Professional Motorsports sponsored by Bimmerworld.Track, Auto-X & Drag Racing sponsored by.General BMW and Automotive Discussion sponsored by Intercity Lines.Quick Navigation 1996 - 2003 (E39) Go Top Now your car may be out of warranty, not a reason to disregard maintenance technical recommendations by BMW. It has been documented for years in BMW TIS and if they recommend using a specific torque range, that is because they designed the engine and know what kind of torque should be applied to the sparks for it to run properly. Now of course BMW recommends using torque for sparks. These are general recommendations by 2 car manufacturers and are nontheless relevant to any other brand. All of these cars are out or warranty now (AFAIK) so if threads strip during a plug change, it's on OUR nickle, not the factory's! Wonder what that would cost?Well yes but on the other hand nobody said we needed to install Ford and Chevy sparks into our bimmers. All of these cars are out or warranty now (AFAIK) so if threads strip during a plug change, it's on OUR nickle, not the factory's! Wonder what that would cost?Īs always: to each their own. Additionally, if you have to worry about getting anti-seize on the tip of the spark plug, and causing the mis-fire Ford warns against, you shouldn't be working on your own car.Īs always: to each their own. This practictice completely alleviates any worries about incorrect torque and the anti-seize keeps the threads in your cylinder head when it's time to change plugs. Their instructions state to run the plug in until the crush washer touches the head, then tighten the plug 3/4 turn. NGK (BMW's factory supplier) does NOT use a torque spec on its plugs. Autolite's statement recognizes the risks of running an plug in an aluminum head w/o antiseize, but both of them seem to be worried more about torque being incorrect on a plug with antiseize. I wouldn't recomend putting Ford (autolite) or Chevy (delco) plugs in your BMW, to start with. Additionally, it helps to clean the threads in the head and on the plug. Always install spark plugs in a cool engine, as hot metal expands and may limit the ability to tighten. Making sure to use the proper torque wrench will help to avoid these types of problems. Damage to the plug’s seals or the insulator can slow heat transfer and cause pre-ignition and detonation. Over-tightened plugs can also cause damage to the plug and to the engine head threads. Poor heat transfer can raise cylinder temperatures dramatically, causing detonation and plug or engine damage. If a plug is not fully seated on the cylinder head, it will not transfer heat effectively and may leak combustion gases. Importance of using the correct amount of torque If you decide to use Anti-Seize anyway, you should be reducing the torque value by 20%. Over-tightening also results in extremely difficult removal. 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. This increases the likelihood of pulling or stripping the threads in the cylinder head. 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. Doing this will decrease the amount of friction between the threads. However, plug seizure is aggravated further when steel plugs are installed into aluminum cylinderĭo not use any type of anti-seize compound on spark plug threads. Autolite spark plugs are nickel plated to resist the effects of corrosion and seizing. This can lead to thread distortion and thread galling If anti seize compounds come in contact with the core nose of the plugs, it can lead to a misfire condition.Īnti seize compounds can also have a torque multiplying effect when installing plugs. Anti seize compounds are typically composed of metallic, electrically conductive ingredients. We do not recommend the use of any anti seize products for installing spark plugs. See below for some additional explanations. Porsche also do not recommend using Anti Seize, along Pelicanpart and many other online resources. But is is not recommended by BMW to use Anti-Seize when installaling plugs. As a matter of fact anti-seize products have a torque multiplying effect. Now I have taken into account that some people recommend to use Anti-Seize. The torque to be used in our case is 30 ± 3Nm, thus 22 Lbf*ft, with a tolerance between 19.9 Lbf*ft and 24 Lbf*ft. I am happy to be corrected if I am wrong anywhere. Some info guys extracted from my blog about proper torque and anti-seize.
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