Hi all,
Came across this interesting article, couldn't find owt in these threads and wondered if anyone has a better understanding, or may have done this mod?
Cheers, Mark
BMW M47 TUD20
Although an extremely well accomplished piece of engineering, the M47 TUD20 was not without it's flaws. A number of common failure points have been highlighted in the engines produced prior to the introduction of the M47 TU2D20, chief among which is 'swirl flap' mechanism employed within the inlet manifold. These consist of a number of butterfly valves within each individual inlet tract. These flaps are secured to an actuating rod via two small screws. It has become clear that over time these screws can come loose via vibration etc. When this happens they can end up being drawn into the respective cylinder, causing significant damage to piston, cylinder head and valves. If unlucky further damage can be caused to the turbo if the screw then makes its way through the exhaust valve into the manifold and subsequently into the turbo. These failures have occurred in such quantity that a number of specialist BMW magazines have featured articles on the problem including information on how to remove the swirl flaps. For those who wish to perform some preventive maintenance on the M47 TUD20 engine, there are companies who supply and/or fit blanking plugs to allow the removal of these swirl flaps altogether. Subsequent revisions of this engine involved the replacement of the mechanical method of securing these flaps by a one-piece moulded plastic flap.
Td4
Came across this interesting article, couldn't find owt in these threads and wondered if anyone has a better understanding, or may have done this mod?
Cheers, Mark
BMW M47 TUD20
Although an extremely well accomplished piece of engineering, the M47 TUD20 was not without it's flaws. A number of common failure points have been highlighted in the engines produced prior to the introduction of the M47 TU2D20, chief among which is 'swirl flap' mechanism employed within the inlet manifold. These consist of a number of butterfly valves within each individual inlet tract. These flaps are secured to an actuating rod via two small screws. It has become clear that over time these screws can come loose via vibration etc. When this happens they can end up being drawn into the respective cylinder, causing significant damage to piston, cylinder head and valves. If unlucky further damage can be caused to the turbo if the screw then makes its way through the exhaust valve into the manifold and subsequently into the turbo. These failures have occurred in such quantity that a number of specialist BMW magazines have featured articles on the problem including information on how to remove the swirl flaps. For those who wish to perform some preventive maintenance on the M47 TUD20 engine, there are companies who supply and/or fit blanking plugs to allow the removal of these swirl flaps altogether. Subsequent revisions of this engine involved the replacement of the mechanical method of securing these flaps by a one-piece moulded plastic flap.
Td4
So no worries for old lumps!!! yes your richt for BM owners of 320d's this is a serious issue.
