2012 ML350 Blutec Oil Cooler Leak Repair
Senior Member
Joined: Mar 2017
Posts: 258
Likes: 50
R320, Astro, JSW, ST4
I would, if I had any suspicion of it not working right.
It has a diaphragm controlling the flow, which breaks.
When this happens way too much venting happens and you get oil trying it's best to come out of every connection downstream to the intakes on the motor.
So, the air connections in the valley, plus the boost hose connections are liable to get greasy/messy.
And the notorious hot oil on the flapper valve motor, under the turbo.
I'd say it's on the 'while you're in there' list, for the oil cooler seal job.
Or, the 'clean the intakes' job - that soot you're finding is made by combining diesel exhaust and crankcase blow-by oil.
And the PCV valve when failing can blow a huge amount of oil, yes.
Good on you again, for the DIY.
BTW, having cleaned a TDI intake of this stuff before I would try burning it out with MAPP gas, rather than using solvent.
Good luck, be patient!
It has a diaphragm controlling the flow, which breaks.
When this happens way too much venting happens and you get oil trying it's best to come out of every connection downstream to the intakes on the motor.
So, the air connections in the valley, plus the boost hose connections are liable to get greasy/messy.
And the notorious hot oil on the flapper valve motor, under the turbo.
I'd say it's on the 'while you're in there' list, for the oil cooler seal job.
Or, the 'clean the intakes' job - that soot you're finding is made by combining diesel exhaust and crankcase blow-by oil.
And the PCV valve when failing can blow a huge amount of oil, yes.
Good on you again, for the DIY.
BTW, having cleaned a TDI intake of this stuff before I would try burning it out with MAPP gas, rather than using solvent.
Good luck, be patient!
