In preparation for an engine swap I started disassembling the engine to part it out. After pulling the heads off I noticed a small amber piece of material in one of the oil drain holes on the drivers side. It was blocking the drain so I removed it. Then I removed the head gaskets and found more of this stuff in the coolant containing areas of the block. I am guessing this material is used in the casting process. Makes me wonder about quality control or lack there of. What do you guys think?
Also makes me wonder if this is why my water pump went out at only 32k miles...

 

pieces of the impeller maybe....shouldn't be there for sure...

 

I looked at the water pump and it has a stamped steel impeller. It isn't the seal for the water pump either.

 

I'm pretty sure now that this was the cause of my water pump bearing failure. I think a piece of this junk got between the impeller and block.

 

It could be a resin type material mercedes uses to stabilize the sleeves, that material wouldnt survive the heat from the casting process.

Although that is kind of weird.

and it still wish our motors were closed deck :/

 

If you found a piece in an oil return hole, then it didn't come from the water pump. (unless it fell there during disassembly) But I can see how it could have damaged the water pump if some where in the coolant side of the block.

James