SEL_69L
Aristocrat
Have been reading up on this engine.
M156 engines were made in house by AMG, they power the
E63, S63, ML 63, CL63, C63, and SL63 cars.
From what I have read (mainly on Benzworld), these engines have two problems that only come up after about 100,000 kilometres.
The first problem concerns the torque bolts that hold the heads down. They stretch slightly (as designed) when a pre set torque is set, during assenmly of the engine.
Problem is, that they can stretch a little more, sometime after about 100,000 kilometres one by one , thus putting extra stress on the remaining head bolts, thus slowly slowly cascading the problem. eventually coolant is noticed in the oil, as the head gasket eventually fails also.
The second problem is associated with the cam cups which contact onto the cam lobes. The metal in the cups is a little softer than it should be, and evntually causes the cams themselves to wear prematurely also. Small particles of metal become suspended in the engine oil, and thus can lead to the premature deterioration of the whole engine.
After 100,000 kilometres the warranty has long since run out, and the repair bills fall on whoever happens to be the current owner. There was a Law suit against Mercedes-Benz, which was eventually dropped by the plaintiffs, because the cars concerned were far out of warranty.
If you are buying any type AMG 63, is becomes absolutely essential that you can prove to yourself beyond any doubt, that the car powered by an M156 engine, has had these problems corrected, especially if it has covered more than 100,000 kilometres. You may be in a lot of pain if you don't.
The M159 engine as found in the SLS was derived from the M156, and these problems were corrected, along with a few other modifications which included a dry sump, as in the M100 engine, decades before.
M156 engines were made in house by AMG, they power the
E63, S63, ML 63, CL63, C63, and SL63 cars.
From what I have read (mainly on Benzworld), these engines have two problems that only come up after about 100,000 kilometres.
The first problem concerns the torque bolts that hold the heads down. They stretch slightly (as designed) when a pre set torque is set, during assenmly of the engine.
Problem is, that they can stretch a little more, sometime after about 100,000 kilometres one by one , thus putting extra stress on the remaining head bolts, thus slowly slowly cascading the problem. eventually coolant is noticed in the oil, as the head gasket eventually fails also.
The second problem is associated with the cam cups which contact onto the cam lobes. The metal in the cups is a little softer than it should be, and evntually causes the cams themselves to wear prematurely also. Small particles of metal become suspended in the engine oil, and thus can lead to the premature deterioration of the whole engine.
After 100,000 kilometres the warranty has long since run out, and the repair bills fall on whoever happens to be the current owner. There was a Law suit against Mercedes-Benz, which was eventually dropped by the plaintiffs, because the cars concerned were far out of warranty.
If you are buying any type AMG 63, is becomes absolutely essential that you can prove to yourself beyond any doubt, that the car powered by an M156 engine, has had these problems corrected, especially if it has covered more than 100,000 kilometres. You may be in a lot of pain if you don't.
The M159 engine as found in the SLS was derived from the M156, and these problems were corrected, along with a few other modifications which included a dry sump, as in the M100 engine, decades before.
