Hi everyone, I have a 2000 Mercedes G290 TD, with original OM602 turbo engine, car has about 300000km, and been driving regularly with no problem. Only thing I noticed is leak of engine oil, and glow-plug light came on dash when I start the vehicle due to the cold weather here in Canada. the other day I topped up some coolant and after driving a bit I felt sudden lost of power, loud noise coming out of engine and huge white smoke came out of the exhaust pipe, I opened the hood, theres liquid splashed everywhere inside, seems like coolant to me. so I drove slowly to home and towed the car to mechanic shop. My shop is not very experienced with this type of older mercedes and previously haven't had any issue with the car other than brake replacement. So they are hesitant to open up the engine to check.
Anyone with any insight to the issue? Any experienced and reasonably priced shop in Toronto area that you recommend I take the vehicle to?
Any help appreciated, thanks in advance!

 

A photo of the engine bay would help. If this happened right after adding a fluid, I would suspect the events are related...