Hi,

I have a 123 diesel and it leaked from the gasket between the oil filter and the engine block. I just tightened the filter and it stopped.

I don't know if the 124 uses the same cartridge type filter in the big can on the IP side of the engine as the 123.

I found it by cleaning and cleaning and cleaning then observing. Walmart sells degreaser for $0.93/big can.

Good luck,
Yoko