EyckVanDyke

Hi all,

I've got an M278 with 38k miles on it that's been slowly losing coolant. I've had to top off the thing every 2.5 months or so, and I'm pretty sure there's a radiator leak along the crimped seal that holds the end tanks onto the radiator body. There are droplets hanging from them after a long drive and I do find a little puddle when I remove the front-most underbody panel, but I'm unable to make it drip-drip-drip when just idling.

I know these are also notorious for driver side turbo lines cracking at the pump-side fittings. Mine look a little sus but i don't see any big trails and isn't where I find most of the "wet" coolant. I snapped some pictures as best as I could, what do you guys think?

Either way I plan on doing them all during my next oil change and major service in 1500 miles or so - new radiator, new turbo lines, new thermostat, maybe a new water pump while i'm at it, new ATF, upper chain tensioners + check ball valves, cover reseal (solenoids and sensors already replaced, with pigtails on both), lower timing cover gasket (to prevent oil and coolant mixing), front main seal, oil cooler gasket.

Let me know what you guys think, are those turbo lines an immediate concern, or can they wait till everything's out and easy to reach? thanks!


Crusted white stuff is dried coolant right? doesn't appear to be an "active" leak tho, nothing's glistening wet but I could very well be wrong.

S-Prihadi

Wow....11 years old plastic section of that coolant pipe and its a goner, albeit low mileage for typical US car.

You wrote :
Either way I plan on doing them all during my next oil change and major service in 1500 miles or so - new radiator, new turbo lines, new thermostat, maybe a new water pump while i'm at it, new ATF, upper chain tensioners + check ball valves, cover reseal (solenoids and sensors already replaced, with pigtails on both), lower timing cover gasket (to prevent oil and coolant mixing), front main seal, oil cooler gasket.

In blue above is what you DO NOT NEED to replace, the rest go for it.
At the rear of the engine, there is a plastic hose assy which goes to the HVAC heater core, that one you best replace.
All of rubber hoses of radiator and aftercooler, that you BETTER replace at this car age ( not miles ).

The oil filter housing assy, its gasket known to fail too and that small black dot they call oil plunger. See below :


Oil plunger




Good luck..........

EyckVanDyke

Thanks! Didn't know about the heater core hose nor the oil plunger, will put those on the list!