'03 C240 New (GMB) Water Pump Leak Mystery
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Junior Member
Joined: Nov 2010
Posts: 27
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From: Maryland
C240 Wagon
'03 C240 New (GMB) Water Pump Leak Mystery
Hello all - I've lurked here and gotten some great tips on DIYs for my 2003 W203 wagon. The engine was making some HELLISH knocking noises when my wife drove up in it last week and I was thinking the worst. I pulled off the air cleaner assy and found some oil in the plug wells that I thought at first was from the valve covers. Closer inspection revealed otherwise.
Did the PCV recirculation system reseal and then while I was crawling around underneath I found coolant leaking from the water pump. Replaced the water pump and gasket with a GMB replacement kit. I was super careful with my install and cleaned the face of the surfaces. Upon start up, the awful noise was GONE but I have a small leak that appears to be coming from the smaller of the two hoses coming from the water pump. (I looked over it carefully and cannot find any other source for the leak.)
The end of said hose that attaches to the pump has a slight bulge below the clamp so I ordered a new one from the Stealer. I did note that the flange where the hose attaches has a slight ridge from the casting that the original pump does not. Could that be the issue? Anyone else have experience with the GMB pump?
Did the PCV recirculation system reseal and then while I was crawling around underneath I found coolant leaking from the water pump. Replaced the water pump and gasket with a GMB replacement kit. I was super careful with my install and cleaned the face of the surfaces. Upon start up, the awful noise was GONE but I have a small leak that appears to be coming from the smaller of the two hoses coming from the water pump. (I looked over it carefully and cannot find any other source for the leak.)
The end of said hose that attaches to the pump has a slight bulge below the clamp so I ordered a new one from the Stealer. I did note that the flange where the hose attaches has a slight ridge from the casting that the original pump does not. Could that be the issue? Anyone else have experience with the GMB pump?
