BMW N43 and N53 four- and six-cylinder spark plugs: fitting and removal

The spark plugs in BMW’s four-cylinder N43 and six-cylinder N53 engines can break or misfire as a result of incorrect removal and installation, which is invisible to the naked eye. Snap-on Tools supplies 3/8-inch Wobble Plus extensions, knee joints and spark plug sockets specifically for this work, which get the job done quickly and efficiently.

The spark plugs of the N43 and N53 engines must be screwed into the cylinder head through a narrow shaft at an angle of more than five degrees. However, the mounting position and the five-degree angle are not visible from above through the shaft. Because the spark plugs are mounted at an angle to the shaft, it is difficult to reach them with a straight extension and spark plug wrench, and in most cases impossible.

Special tool for BMW N43 and N53 spark plugs

Sometimes people try to fit a normal straight spark plug wrench onto the spark plug using brute force and sometimes even a hammer. Because the spark plug is mounted at an angle in the cylinder head, lateral pressure is exerted on the insulator. This causes the spark plug to crack, break and, when the engine is running, the spark can jump to ground.

Various spark plug manufacturers have issued service bulletins about this phenomenon. However, the service bulletin has not reached all car companies and workshops by any means.

Snap-on Wobble Plus and spark plug wrench with knee joint

For BMW N43 and N53 engines, where the spark plugs are mounted at an angle, Snap-on offers 3/8-inch Wobble Plus extensions, knee joints and spark plug sockets. A wobble extension has a drive square at the end on which – in this case the spark plug socket – can pivot (move) 16 degrees relative to the extension. Thanks to the clever design of the drive square, sockets can also be fixed to the extension with a simple click.

Want to remove and install spark plugs from BMW N43 four-cylinder and N53 six-cylinder engines without any hassle? Ask your Snap-on dealer for the straight 14-millimetre 12-point spark plug socket (order number: S9714MK) in combination with the 3/8″ Wobble Plus extensions (order number: 206AFXWP) or spark plug wrench with knee joint (order number: S9714MKDFUA).

Source and image: NGK